Test kits are like loaded guns. What if the test is bad or you messed it up?

I like to confirm test results. Your fish aren't gulping air? Ammonia is basically 0. This test was done on an established pond? I'd like to know the number/size of fish and how much you feed and age of the pond, but I see no reason to believe a couple of tests from a single person and kit. I like stuff to make sense before going linear.

The other red flag to me is this test was done out of the blue. That's super dangerous imo.

The Stress Zyme does nothing for you. This is an established pond (it sounds like). That means if there is nitrite present in the water the bacteria that eat it are also present (they're always present in every pond on the planet). So that would mean they haven't been able to eat the nitrite and reproduce. Adding more bacteria doesn't change that. Plus, in new tanks it still takes nitrite eating bacteria to start reducing nitrite. But adding may not hurt anything much either.

Adding stuff to a pond because someone told you and not understanding the product is a great way to turn healthy fish into unhealthy fish.

If you have to ask how much salt to add I don't think you should be adding any.

If you are really, really freaked out, don't want to confirm the test, the safest thing I think you can do is a complete water change because this is a 300 gal pond. Doing a 50% change has almost all the danger of a complete change so I don't see much more risk in a 100% change. Treat it like you would a new pond start up.

But I wish you would confirm the test before doing anything more. Test your tab water. Test a friend's pond. Take a water sample to a pet store.

Because the fish aren't currently in trouble, and this test was out of the blue, if there is high nitrite it means the fish have been dealing with this for a long time. An extra day or two is probably not as big a risk as it is to do all these massive changes. Hopefully you're well versed in doing massive water changes, know the pH, water temp, etc., of the source water and what's in the pond and know about dealing with chlorine if needed. Many people don't and the fish are dead the next day and blame the false test and not the actions taken.

I have done water changes before and make sure I add the new water slowly trickling over the waterfall and I do add chlorine/chloramine remover. I actually thought partial water changes were good, although I usually only do about 25% when I do them. I have not had dead fish for any reason other than them getting caught in a homemade filter twice (quilt batting can be dangeious when it gets clogged up and creates a vacuum), and a heron, and that is over a 10 year period. The pond is established, the original was a 150 gallon preformed that I enlarged several years ago and replaced the the performed with a flexible liner. The old filter was just replaced with a new one 2 weeks ago, and it has a UV filter, which I have never used before. Because of the new filter and the addition of a UV I wanted to keep a closer eye on things, hence the test kit. Best as I can count with them moving around so fast, there are 13 fish, all goldfish, in the 3-6" range.

Oh ya, my tap water usually runs around 8.0 for pH, but I just checked it with this kit and it was 7.8.

Not really freaking out, just thought the water changes would be safest. I have the salt because I did experiment with using it years ago, still have a salinity test kit that is probably a decade old as well. Haven't used it or felt it was necessary for a long time. Some people use it, some don't and it doesn't seem to be critical either way, but once again, haven't used it in years. The most important things I learned in my first years with a pond was read more, do less. I still have my old filter going, I just don't think it has been enough for the larger pond with more fish, and the only thing worse to ME than pea green water is dead fish. I am most concerned about the addition of the UV because I have never used one before. I didn't think adding a new biological filter while keeping old one going would be harmful, esp. since it usually takes a biological filter a while to get going and it should be a relatively gradual change. I did turn down the UV to run only 6 hrs at a time.

Sounds like you know what you're doing...hard to tell sometimes.

If the pond was green when this new UV was added it could explain nitrite. Maybe there was high ammonia a few days ago and the nitrite bacteria aren't caught up yet. But still I would really try to confirm. If you've done a 50% water change what did that do to the nitrite? I'd test the source water for nitrite too.

For 300 gal I assume there isn't a 2" layer of muck on the pond bottom. Decay can produce nitrite, but to me that's a real long shot that I wouldn't bet on, especially to produce high levels.

You're in summer so the bacteria have been in their optimal growing cycle for way long enough.

I'm just having a hard time seeing where you would be getting a high nitrite reading which makes me question the reading.

As to how much salt to add...I assume by now you already researched this and I think that's the best way. Better info than just posting 300 gal = X salt.

It would change things imo if your fish are started gulping air or show signs of brown blood disease. But even then, for a 300 gal pond, and you know what you're doing, I think a full water change it the best bet. Salt is more useful when a pond is large and a quick water swap really isn't possible. But you are in the best position to make that call.

The UV isn't interfering with anything. Some people do think the UV kills the nitrite eating bacteria but that's been tested a lot and as always shown no effect on bringing new bio filters up to speed. The bacteria doing the eating create a bio film for themselves, jelly like stuff, so they can stay anchored. When they reproduce, because there's more food (nitrite) the new bacteria do float around and some no doubt are killed by the UV, but many apparently aren't. They live in a very strange world to us. But if you wanted to turn the UV off there's no harm to that either. Turning it on and off I don't see any benefit, but no harm.

To me a 25% water change is a massive change, but I'm a pond person. You're really more in the aquarium world at 300 gal. 13 goldfish 3-6" in 300 gal could be getting more toward the higher fish load range depending on how much you're feeding. That makes me look at this as more of aquarium as far as testing and water changes go.

If possible I would net the pond with even a 25% change to stop jumpers. Never know.

I wish you luck and hope it all turns out. It would be good to hear back what you learn.

I need to get to work, and I don't have time to retest this morning. I will do that this evening. I have a very sick family member in the hospital, so the pond is not top priority. But, as I said, its been a long time, and I obviously do not trust my memory, nor consider myself an expert, which is why I came here for advise, and I do appreciate your taking the time to give it. I have not added salt yet, or done that research again. I am glad to know the UV will not interfere with the bio filter. But I remember you mentioning on another thread that the green water was helpful and suddenly getting rid of it could create problems, such as high ammonia levels, which I then assumed would lead to high nitrite and then nitrate levels. I hope I got a bad nitrite reading. Honestly, it never occurred to me tap water might have a high nitrite reading, but that possibility is interesting, so I will check that as well. I will follow up with more testing tonight.

This post was edited by sue_ct on Sun, Jul 6, 14 at 6:23

That's why I asked if the pond was green when the UV was added. It seems like a long shot, but worth a mention.

I think you already understand this but just to make clear...the green sucks up the ammonia. Green dies and ammonia starts building which causes bacteria to grow to eat the ammonia which takes about 7 days for the bacteria to reproduce enough to handle the ammonia. The eaten ammonia produces nitrite which makes the bacteria that eats nitrite to reproduce which take longer to reproduce.

The higher the fish load the faster the ammonia builds. In real high fish loads the ammonia can build to deadly levels before the bacteria have a chance to reproduce enough and the fish die. In really really high fish loads the build up of ammonia can be so fast that even the bacteria, both ammonia and nitrite eating kinds, have a hard time reproducing and staying alive.

But I know that didn't happen in your pond because ammonia tested basically 0 and you're not saying the fish are acting funny.

In most cases the ammonia builds slowly, or not at all, stays safe, for about a week. And then maybe there's a little nitrite which which goes away say a week or two later.

So getting a high nitrite reading with zero ammonia doesn't make sense. Makes me question the test. Not dismiss it of course, but I'd want more info.

You'd have to be in a very small window where your fish load is creating a lot of ammonia but bacteria was able to reproduce fast enough to keep fish alive and get ammonia down to 0. So now the bacteria is converting all ammonia as it's being created and producing nitrite but the nitrite converters haven't come up to speed yet. It is possible. Nitrite converts are slow to reproduce.

Ammonia is the pretty fast killer. Nitrite you have some time if the fish appear normal. In many ponds there is likely a spike in ammonia and nitrite at different times of the year, when green clears, or other causes and because the owner doesn't test the fish sail through without the owner noticing any difference. The bacteria get up to speed and everything is fine.

I am a day late and a dollar short here and I really can't add anything to what waterbug_guy suggested but one thing I like to do with the colour comparison tests when the readings are high is dilute the water and test again.

For instance take a cup of your pond water that is showing 2 ppm nitrate and 3 cups of bottled water (or tap water if you are sure it tests 0 for nitrite) mix them together and test again, if the result is .5 ppm then you can have some confidence in the first test result, if not then you may need to try both tests again.

OK, not sure you will be able to draw any conclusions here because conditions changed. When I got up this morning, the GFI outlet had tripped and pumps and filters were not working. I reset it and they were all working when I went to work. I just go home about an hour ago and again it had tripped and I reset it. Will need to trouble shoot that. I have no way of knowing how long there was no filtering today. I would expect Ammonia to be up a little more, but I just tested, and it was clearly 0.25 ppm. Then I tested Nitrite. That was also 0.25 ppm. With the water change (I did do 50%) and the lack of filtering I can understand not so much nitrite, but that is a big change. I have not retested anything else but I can if it would help.

OK, I did retest nitrate and it was also 0, as I expected. ph was still around 8.0.

Since the biologic filer was not running consistently to change the ammonia to nitrite, it would not have gone up again after the water change, I think. But since the Ammonia did not go up very high either, maybe it had little overall effect?

Still need to do some morning tests.

This post was edited by sue_ct on Sun, Jul 6, 14 at 19:29

Got a morning test this morning, but no change. pH stable at 7.8-8.0, ammonia 0.25, nitrite 0-0.25, and tap water I checked as you suggested (still don't know why it would be high in nitrite) but it was 0. I will order the KH test because I think it would be easier, if it would help.

I keep forgetting to mention that the day before I did this test I moved a couple of large plants around. One had split throught the pot and is just growing along the pond bottom. That is the only stuff on the bottom, no muck or dirt or anything anywhere else. But the one still in a pot was a little stinky when picked it up. I was thinking about taking it out of the pond and removing any mushy leaves and maybe rinsing it off before returning it. Would stirring that stuff up have cause the nitrite to go up?

I also was able to find in a gardening journal that I enlarged the pond to its current size July 6, 2007. So it is now 7 years old.

I am going to keep testing frequently until I am ready to take the old filter out, which won't be until I get at least 2-3 tests with 0 Ammonia. Then I will keep testing again until I know it is stable and Ammonia and nitrite are not going up. Any other advise about how to be sure the new filter is adequate to take over before removing the old one?

For drop tests I consider 0-0.25 to be effectively zero just because it's hard to tell with the colors. Close enough.

I wanted you to test source water for nitrite because I have no idea where you're getting your water, you have a test kit and I was trying to figure out any possible way the 2-5 ppm nitrite could have made any sense. I didn't expect your source water to be high in nitrite but it's simple enough to test in order to actually know. Understanding you source water is every bit as important as understanding your pond's water imo.

So nitrite is now 0. To me that tells me the earlier reading of 2-5 ppm was false and that the pond never had high nitrite. A 50% water change wouldn't drop nitrite from 2-5 ppm to 0 and it's very unlikely bacteria would suddenly convert it all. And I didn't a single reason that would support high nitrite.

That's why imo these tests can be extremely dangerous. They often lead people to do extreme things and put fish into actual danger.

The little bit of stuff in 2 pots is sure nothing I'd worry about. The foul smell is completely normal. If you had 1-2" of muck on the bottom it could have explained nitrite, but even that would have been a pretty crazy long shot. Although muck can produce nitrite it does in such small amounts it's almost never an issue in backyard ponds. More of a thing in farm ponds feeding lots of food.

Dechlorinating water can create ammonia, but products also contain an ammonia binder so it's safe. So seeing ammonia after a water change is nothing to worry about. You just want to see it drop over the next week and not increase from the initial reading. Your case is like most, even with a 50% water change you don't read any ammonia...because the algae suck it up so fast and it never was that much anyways.

I'm not sure what kind of filter you're adding but if this is a bio filter there's nothing for you to do because you have 0 ammonia and nitrite so there's nothing for the filter to do. A bio filter is needed when water is testing something above 0 for ammonia and then you can daily test to see ammonia fall and nitrite raise and then nitrite fall and nitrate raise...in theory. To actually see those results can be difficult especially in a Water Garden. In high fish load ponds the filter can be pre-cycled by adding drug store ammonia and forcing the issue. What often happens in Water Gardens is they see ammonia drop but never see nitrite or nitrate. They scratch their head for a bit and then pat themselves for having a great bio filter. But the reality is algae consumed the ammonia so there won't be any nitrite or nitrate to measure and the bio filter is never actually needed. But people like to think they're the ones keeping the fish healthy. Algae doesn't get credit for anything.

If you really really wanted to pre-cycle a bio filter you can do it separately from your pond. You just get a tub of water you can pump thru the filter and back into the tub. Then add drug store ammonia to get the water up to say 3 ppm and keep it there until you start reading nitrite and then stop ammonia and wait to see nitrite fall and nitrate climb. Then you know you have a bio filter with lots nitrifying bacteria. However when you put it into the pond most of the bacteria will die over time because of a lack of food.

I'm expecting you to have KH in the 20-70 ppm range. That could be considered by some to be too low, others would say perfect. Test your source water too. If you're doing water changes from time to time I wouldn't bother fighting your source water. If it's 30-70 ppm KH then just accept that for your pond too. If KH is below 20 ppm then it might be worth getting it up. Totally your call on how much you want to do.

In high fish load ponds keeping KH higher is more of an issue because they have bio filters and the bacteria converters produce acid which drives down pH and so pH crashes are a much bigger risk for them.

But there's no harm in keeping your pond's KH up at 150, 200 ppm or whatever if you like. Small fish load Water Gardens don't have as high a risk for pH crashes, but keeping KH up can reduce that risk even more. Just make sure ammonia is 0-0.25 ppm before raising KH just to be safe.

Source water is town water. The new filter is a biofilter with UV, cannister type as someone called it, with bioballs. I have a 750 gph pump feeding it and then going to the waterfall, by which time it is really probably more like 500gph, if that. There is no visible algae now. That doesn't mean they aren't there, just no green water. No string algae. There is always some algae on on the liner and rock waterfall. So does the bio filter having nothing to do or is it just doing its job? Without the filter I had pea green water, again what I was concerned about the most was that the pond had cleared so not much help from algae any more.

Try to ignore the tubing. It goes to both filters, the smaller, older of which I just removed. Once the pond is stable, the new larger filter will be hidden. I am going to have to start discarding Hyacinth so I can see my fish in my new clearer water. But since I am also dealing with the ants, I have been moving rocks and have exposed pond liner, which does not look great.

The Nitrite looks bluer in this photo, it looked more purple to me at the time, but it is still pretty dark, no nice and light turquiose to lt blue like it does now.

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This post was edited by sue_ct on Tue, Jul 8, 14 at 18:30

It sounds like the bio-filter is starting to do its job. The UV sterilizes the water killing the green algae so you can see your fish, absent the single celled algae (or GWA for green water algae) there is nothing to take up your fish waste and this is what the bio-filter is for.

With clear water, a new bio-filter and no GWA you should see your ammonia levels slowly rise as the first colony of beneficial bacteria is getting established, these bacteria convert Ammonia into Nitrite. As the colony grows your ammonia levels should stabilize and then start to drop but as this happens your nitrite levels will begin to rise. As the nitrate levels rise they provide food for the second batch of beneficial bacteria that will convert the nitrite into nitrate, once that colony is established the nitrite levels will follow the ammonia levels and start to drop. Nitrate (at normal pH levels) is much less dangerous to your fish than Ammonia or Nitrite. Rising nitrate levels can be dealt with by water changes or by being absorbed by fast growing plants (Hyacinth is a popular choice). If your bio-filter is adequate to your fish load once it has cycled you should expect to see ammonia and nitrite levels at .25 or lower.

This cycling of the Bio-Filter happens again on a smaller scale when you clean the filter and every spring (anywhere the pond freezes anyway).

As an aside I find lot of people have problems when cleaning their bio-filters, the media (in your case the "bio-balls") is supposed to provide a home for the bacteria, scrubbing it off is counter productive. If you have to clean it simply remove the filter media and rinse it lightly in a pail of pond water. you will still end up having the three waves of ammonia/nitrite/nitrate but they will be shorter and smaller than the original cycle, if you are concerned about them cut your fish feeding in half for three or four days after cleaning.

So does the bio filter having nothing to do or is it just doing its job?
No way to tell currently. My guess is the bio filter is doing nothing just because of your kind of pond, fish load and filter type. Those types of filters (submerged static media) aren't very good at converting ammonia. There's no reason to do this but to tell you disconnect the filter and see if ammonia increases.

It sounded to me like you were wanting to add a new filter of some kind??? That would do nothing because ammonia is currently zero. Nothing for more bacteria to eat.

Without the filter I had pea green water, again what I was concerned about the most was that the pond had cleared so not much help from algae any more.
I had asked a few times if the pond was recently green, so I guess it was. You are right, algae consume ammonia so when a pond goes clear ammonia should be tested to make sure the pond can handle the ammonia load.

Only the UV part of the filter has anything to do with clearing green water.

I couldn't tell anything from the pic of the test results. I go by the values people post. Unfortunately it's really hard to get people to post actual numbers. Don't know why.

Sounds like everything is fine?

I am not sure what numbers I could have posted that I have not. What numbers are you looking for? I thought you said 13 fish 3-6" long was a high fish load for a 300 gallon pond. But I could have clear water with just the UV with no biofilter and that fish load and no ammonia build up? I thought that you either needed the green water or a biofilter to keep ammonia from building up. So your theory is that I could just use a UV and keep all my fish and have clear water and no problems? I thought I understood a lot of this but now its getting confusing. I posted pictures because I thought you said you didn't know what my pond was like or something. Now you think its hard to get people to post numbers and I have posted every number I have unless there are numbers you are missing that I am not aware of? Like I said I thought I understood the basic process of waste-ammonia-nitrite-nitrate, but I don't get that. I do have hyacinths which help, but it has taken a couple of months for them to fill in like that, so I can't imagine leaving 13 fish in a pond that size with a UV and no filtering for a couple of months in warm weather and feel confident that they would be fine. So I guess I need more educate about it after all.

AWJames54, there is no need to clean the filter as you describe, which is why I purchased the filter I did. It has a backflow function, so basically you turn it to "clean" and the filter reverses, stirs up the bioballs and cleans them by shooting pond water through the filter and out a separate discharge hose into my garden next to the pond,instead of down the waterfall and back into the pond. Hopefully, watering the flowers and providing a little fertilizer at the same time. They suggest removing the bioballs and leaving them in the pond in a mesh bag or something over winter to speed up reestablishing it in the spring.

This post was edited by sue_ct on Wed, Jul 9, 14 at 19:14

I am not sure what numbers I could have posted that I have not. What numbers are you looking for?
You posted a pic of the tests but no numbers. Personally I would like to see what you see, meaning result of every single test you made as you made them. Not important now. As far as I can tell nitrite is 0 on the last test...sure be nice to get confirmation of that. Lots of posters type nitrate when they mean nitrite.

I thought you said 13 fish 3-6" long was a high fish load for a 300 gallon pond.
I said
13 goldfish 3-6" in 300 gal could be getting more toward the higher fish load range depending on how much you're feeding.

But I could have clear water with just the UV with no biofilter and that fish load and no ammonia build up?
Sure, it's possible. You know by testing. Even if your bio filter is needed you still have to test ammonia a couple times a year to see if the ammonia load is greater than the pond and bio filter can handle. Testing is the only thing that can ever tell you.

Since you posted pictures I can see the kind of pond you have...a Water Garden. Lot's of WH, lots of algae (even if you don't see it)...I have no idea how much food you feed but my guess is light...the type of bio filter you have...your test results...total that up if we were in Vegas my money would be on your bio filter isn't needed. Just a guess. Since it's already there's no point in removing it. It is purely an exercise in understanding ammonia/nitrite and what role a bio filter plays.

I thought that you either needed the green water or a biofilter to keep ammonia from building up.
There are other things that consume ammonia.

Green water is as good a bio filter as there is ammonia wise. It's difficult for ammonia to get past all those algae cells without getting eaten.

Green water is a good bio filter because algae are plants. Green water algae is not the only plant in your pond. You have other algae and the WH which all consume ammonia.

A bio filter can be a good bio filter, but submerged static media like yours is at the bottom of performance. My guess is most ammonia in your pond doesn't get much chance to get to your bio filter. The inside of your pump and pipes are excellent bio filter because muck can't settle very well in the fast moving water and bacteria love the fast moving water because it brings more food.

So your theory is that I could just use a UV and keep all my fish and have clear water and no problems?
Basically yes as far as ammonia goes. Ponds do change over time. But I'm sure not saying you should remove your current bio filter.

My thinking....

Green water = 0 ammonia = no food for the bio filter so bio filter is doing nothing.

Green water goes away...if ammonia went up for a week or so there would be food for the bio filter and ammonia then goes down means the bio filter may be needed. As far as I can tell this never happened, instead the ammonia was sucked up by the WH and other algae. So to me those are your current bio filter.

To be clear...I have very, very little confidence I understand your pond very well at all. I get the idea the pond was green at some point and is clear now but don't know the time frames. Don't know the time frame when you started testing. And lot's of other things. Not asking to know that stuff now because this seems to all now be a non-issue.

I thought I understood a lot of this but now its getting confusing. I posted pictures because I thought you said you didn't know what my pond was like or something. Now you think its hard to get people to post numbers and I have posted every number I have unless there are numbers you are missing that I am not aware of?
I assume you've done more than a dozen tests over this period. Kind of sounded like that, but I don't really know. I would have liked to get all those numbers. I'd like people to start every post with a list of all their latest test results along with ppm or whatever scale they're using. But that's because I hate guessing and assuming when trying to help someone.

Like I said I thought I understood the basic process of waste-ammonia-nitrite-nitrate, but I don't get that. I do have hyacinths which help, but it has taken a couple of months for them to fill in like that, so I can't imagine leaving 13 fish in a pond that size with a UV and no filtering for a couple of months in warm weather and feel confident that they would be fine.
There's no reason to remove your bio filter. Whether it's needed or not, you already have it. I thought you were wanting to add more bio filter or a different one. Maybe not, I have no idea at this point.

There's really only one rule...if something changes that effects ammonia I think it's a good idea to test for ammonia to see if you have a problem. That's it. More food fed, fish grown, fish added, plants removed, string algae dies, green water dies, bio filter breaks, pond drained and cleaned, etc.

The complexity comes in when people think their bio filter is the only thing consuming ammonia.

Forums are a pretty bad way to communicate. Face to face has a ton more info. It's frustrating at both ends. But this is what we have.

Sounds like everything is fine. So good deal.

Thanks. I posted every test result I have done. The photos are of the original test results with the high nitrite that you thought were in error. Pretty much a non issue now. But if you go back in my posts my test results are there for July 5, 6 and 8th. I can't test more than once a day because of work. I also tested on the 9th but did not post them because they have not changed.

The backwash is a nice feature, many people would get in trouble with that type of filter because cleaning was such a PITA they wouldn't do it on time, the filter would start to clog and the water would cut channels through the media making the filter a waste of time.

Putting the bio-balls in the pond over-winter is also what I would recommend.

As an aside I am assuming the UV is after the filter chamber and the last part of the process before the waterfall. I've never used UV, when it first started showing up for hobbyists it was expensive Voodoo, only years later did it become well enough understood (and affordable).

As for the nitrogen cycle I think you have a pretty decent understanding to this point, just remember that every surface in your pond including liner, plumbing and even the roots to the hyacinth are home to the nitrifying (sp?) bacteria.

The one thing that hasn't been discussed is how much you feed your fish, that has a huge impact on how much waste they produce and therefore on ammonia et cetera.
It may well be that you have enough going on in your ponds environment that the canister filter isn't really doing much but keeping a log of your test results will help tell you how much it is doing. Make a note of the changes in readings from say one day before and then two, four and six days after you backwash your filter.

It is absolutely possible to keep a pond crystal clear with just a UV system and frequent water changes .. or for that matter just with frequent water changes. It is also possible to keep a pond crystal clear with just a Bio-filter and not nearly as frequent water changes.

As for the nitrogen cycle I think you have a pretty decent understanding to this point, just remember that every surface in your pond including liner, plumbing and even the roots to the hyacinth are home to the nitrifying (sp?) bacteria.
Also important to remember is the WH consumes ammonia directly.

Many people are very focused on the nitrifying bacteria which is important in aquariums, Koi Ponds and fish farms. But for Water Gardens and many other pond types that have WH and algae the nitrifying bacteria are much less important because the main consumer of ammonia in these ponds are the plants.

Thanks, I do always notice an improvement once the WH really get started each year,but until the last couple of years, I was able to clear it before then with just a biofilter and mechanical filter. I used to use a hommade mechanical filter by placing the pump to the biofilter in bottom of a bucket and then fill it with lava rock and top it off with several layers of quilt batting. I am so looking forward to not having to resort to that with the UV. As I previously mentioned, I lost a couple of fish because the batting became clogged and created a vacuum that a fish got stuck in. It was very high maintenance in very green water to keep that going. Thanks for all your help, advise and reminders. I will keep testing at least past a couple of cleanings to see what happens.

My feeding habits are very sporadic. I feed them for pleasure, not because I have any misconception that they need it to survive. They go weeks without any feeding and do just fine with what is naturally in the pond. But when I am on vacation and home more they get fed regularly, and actually, the day before the high nitrite reading was probably the first time I fed them three times in one day. It did occur to me it might be related, but with all the talk about it not being reliable because of the lack of ammonia I kind of dismissed it. It was only one day and I had previously been feeding once to twice a day, which I continue to do with no problems. I would rather expect an increase, but not a huge spike from one or two extra feedings. But I have never really tested that theory. Since I am doing regular testing now, if I get another spike I will be able to relate it more closely to whatever
feeding I have been doing.

Almost forgot, no the UV is before the biofilter, the premise being that the dead algae will supposedly be removed or at least partially removed by the biofilter before the water exits into the waterfall and back into the pond.

This post was edited by sue_ct on Fri, Jul 11, 14 at 18:32

Measuring 2-5 ppm nitrite only means the test shows 2-5 ppm nitrite. Doesn't necessarily mean the pond has 2-5 ppm nitrite. There was only one thing pointing to 2-5 ppm nitrite...a single test. The fish showed no sign, ammonia was 0 and the most important indicator is a follow up test showed 0 nitrite after a 50% water change after what sounded like a really short time frame, day or two. There is no way nitrite can drop that fast. Therefore the first nitrite test was an error. It happens.

At least that's how I read the posts.

Tests are only tools. When test results don't make sense they should be confirmed by other means imo.

Next time, if there is one, I will repeat the test immediately. That way will know conditions and water haven't changed. But it certainly does look that way.

Finally got my KH/GH test kit today, although filled with glass from the smashed test tube inside. Fortunately, I have enough extras.

Pond:
KH - 100

GH - 200-400

Tap Water:
KH - appox 120. 1 drop more of the solution required than the pond.

I repeated the KH test and got the same results, and it seems a reasonable level.

Your KH is good. Ideally 120 or above is best but since your pH seems to remain stable...that is what is important. You really only need to aim to raise it if you have unstable pH or if you are running a bead filter - then you want it at 200 or above.

You said that you replaced your old filter with a new one and my experience/guess is that DID have a nitrite reading that high. You may have taken the reading right at the "tipping point" where your new filter fully cycled. You did a WC and the nitrates kicked in also (though they show as 0 b/c of your high plant load) and so now you think you are crazy. LOL

Keep an eye on the nitrites still. Watch for any fish hanging at the waterfall...any red, streaked fins. If your nitrites are bouncing around, dose your pond with salt to .15% (note the decimal) until they consistently stay at zero.

This level of salt won't harm the plants and will protect your fish against brown blood disease. If you are using water softener salt, make sure it isn't the one w/ additives in it to inhibit clumping. Just pure salt.

As you already know, you are seriously overstocked. :) I am too. lol Just remember to really maintain rigorous water changes and think long term about more ways to increase/improve your pond size or filtration (maybe a sand and gravel filter or shower filter).

Thanks, ademink, your thought was mine initially, which is why I didn't automatically assume an error. It is not a difficult test to perform. But I really can't completely rule out an error on my part, so each person can draw their own conclusion, lol. It does't really matter that much now because it has stable since then. I am always on the lookout for fish coming to the surface for air or hanging out there. One fish near the waterfall would not usually set off alarms for me, but if multiple fish started doing that I would definitely take notice. My pond was so stable for so many years I stopped testing. Even now, 10-15 years later, my pH has not changed significantly. Since the fish seemed healthy, I wasn't worried until I made the current changes. I used to salt the pond years ago, but stopped because although I knew it was supposed to help decrease the incidence of disease, I was not bringing in new fish or seeing any problems, so I stopped that as well. I do have salt with no additives, I made sure of that when I bought it, since it was for the pond then also. I don't have a water softener. I just hope if the Heron comes back he doesn't pick my largest, oldest fish again. I was using a net, but it does detract from the pond. Of coarse that is a natural population control, but I don't want to loose them all, and that could also happen. Plus, I feel protective of them, like pets, lol.

I am reading this thread and was wondering what actually is a bio-filter? Would water pumping through a skimmer into two pea gravel bogs that were heavly planted w plants be considered a bio- filter?

Since your source water has good KH it explains why you don't have pH issues.

I know in ponds forums it is standard practice to say nitrite = salt treatment. That's unfortunate. For a 300 gal pond and a keeper who is experienced with water changes I don't see why salt would be a good choice when a large or complete water change is so reasonable. Salt is used when water changes aren't reasonable, like fish farm ponds, large ponds. Salt has drawbacks, like it has to be monitored and adjusted. Plus the nitrite is still present, salt only slows the damage to fish.

In either case (salt or water change) it's important to increase O2 (assuming not already done) with an air pump until the fish have a chance to replace the damaged cells. Without increasing O2 fish can still die even with salt or water change.

You said that you replaced your old filter with a new one and my experience/guess is that DID have a nitrite reading that high. You may have taken the reading right at the "tipping point" where your new filter fully cycled. You did a WC and the nitrates kicked in also (though they show as 0 b/c of your high plant load) and so now you think you are crazy.
All things are possible, but...a 50% water change should have reduced nitrites from the tested 2-5 ppm amount to 1-2.5 ppm. In 24 hours nitrite went to 0. That's about as close to impossible as it gets. Nitrite converting bacteria aren't known for speed. Plus nitrate tests 0. I know people think plants are tremendous but for all this to happen in 24 hours...there's just no other way to put it...is unbelievable.

But if people want to believe a single test and start throwing all kinds of cures at their fish, or believe forum posters telling them to do so, then I say super, have a ball. This is a hobby for our enjoyment and if some drama adds fun then I sure don't want to get in the way. Lot's of people add unneeded complexity to their ponds and seem to enjoy it greatly

Waterbug_guy, I decided years ago that I prefer the KISS method to water gardening, which is when I put away the salt and testing kits. I decided not to fight the natural water conditions I had, although way back then there all kinds of people telling me to do something immediately to drop my pH which they felt was too high, add salt, and test daily at least. I decided that was not what I wanted, and my fish and I have been content with that decision for about a decade. So I certainly agree with a lot of what you have said. You are also certainly more knowledgeable than I about how much the actions I took could have altered my test results. I can not rule out user error because no matter how simple the test I am simply cable of erring. But my initial thought WAS that my ammonia had been high and the filter was kicking in and taking care of it, and the water change and plants helped. But I am not disregarding what you said, because I am just not as up on testing and treating those results, in part because I chose not to g0 that route years ago. Like I said, it really doesn't seem very important any more. But I am going to continue testing at least a few times a week for a while and will try to remember to do it right before and after cleaning the filter. I would be interested to see what the results are before starting the filtering next spring with the fish load I have, as well as from the time I start filtering until the WH take off again next year. I wonder if I am having periods of high ammonia levels before the bio filter really gets going again, when I only have a few small WH. Something to maybe keep an eye on in the fall once a frost has starting the kill the WH, as well. Especially once I put the filter away for winter.

Joecd, as far I am concerned any filter that harbors the good bacteria that can change the ammonia in the pond to nitrite and then nitrate is a type of bio filter. There are almost as many ways of doing that, it seems, as there are people with ponds. One way is to purchase a canister type filter that has media inside for these bacteria to grow on, as I did. There are also many types of homemade biofilters, and most surfaces in your pond probably do that to some extent, as a well. But most people I have heard referring to a biofilter are referring to a separate filter that is specifically designed to do that, whether it is a purchased filter or a homemade one, rather than to the natural bacteria on the surfaces in the pond.

I've had filters that have gone from 5ppm to 0ppm in 24 hours when they cycled. Nitrate can test at 0 when there are a lot of plants.

Salting to .15% for nitrite protection isn't what I would call "throwing all kinds of cures". It isn't a high level of salt and it is the only time that I even use salt in a pond or QT.

Always good to offer advice and be insulted for trying to help someone. You seem to have all knowledge needed here waterbug guy so I'll take my 10 years of ponding experience elsewhere.

I've had filters that have gone from 5ppm to 0ppm in 24 hours when they cycled. Nitrate can test at 0 when there are a lot of plants.
I don't doubt that you think that. The question is whether it is possible for that all to take place in 24 hours. It isn't.

I'm sorry you feel insulted that your claim was questioned. If you separate your beliefs from yourself it's much easier to discuss things and learn. I've had hundreds of my beliefs about ponds questioned over the years. I don't get hurt, mad and run away...I ask questions. Most of the time the person questioning doesn't know what they're talking about. But once in awhile they do. They explain what they know and give me terms that I can research. If it checks out I simply change my view and start posting the new info. It's not my info, so I have no problem dumping bad info and using better info. But I do understand most forums are for people to just use personal attacks to be right. Which is why you will almost never see biologists, veterinarians, etc., posting in Water Garden forums. It's pointless to take and give better info to people who don't want it. They just want their beliefs confirmed by like minded people.