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Using Hydrogran Peroxide...

Posted by hardin 7 SE OK (My Page) on
Thu, Jun 18, 09 at 8:48

I have read posts re: use of HP 3% in ponds to clear algae. I've noted that it works on string algae, but will it work on the floating algae (pea soup)? Mine isn't bad, just making water murky enough that its hard to see and its a little annoying. I had thought of also using barley straw, but it says to add before algae starts, that it will not work after algae is already present. Thanks.

Follow-Up Postings:

RE: Using Hydrogran Peroxide...

Hi hardin,

Here is a post I saved from another forum because I thought the responding poster was very knowledgable. Also this was posted on a public forum so I do not think the posters would mind it being used again. I have never tried this and personally I am very cautious and do not add chemicals to the pond unless necessary.


Originally Posted by BillJ
Roddy,how much HP can safely be added to 4000 gal.?And how often?Doesn't it temporarily lower ORP?If so,how long before the Orp returns to normal,or does this only occure when neutralizing PP?
Not even close to giving up yet. Thanks,Roddy

How much hydrogen peroxide can be safely added is a function of the concentration of the hydrogen peroxide and the robustness of the pond's biofilter.

I add typicallly 50 ppm to 100 ppm hydrogen peroxide when I add it. That kills algae and cleans water and cleans the bottom of the pond just swell, and doesn't hurt fish. It doesn't hurt my lava rock fountain, biofilters in my water gardens. Ammonia and nitrites stay non-detectable. I don't turn off the biofilter flow when dosing the hydrogen peroxide.

100 ppm hydrogen peroxide is a quart per 1000 gallons using the 35% hydrogen peroxide strength, or 11 quarts per 1000 gallons of 3% hydrogen peroxide from Walmart (or other Drug store sources). While that is what I dose, since it is also a documented treatment that kills several of the common fish parasites, I wouldn't recommend doses much higher.

The hydrogen peroxide is gone in 24 hours, most of it is gone in about 8 hours. When you first dose it, the sediment boils up from the bottom of the pond so have a fine net to remove it from the surface for the first 30 minutes or so after dosing the hydrogen peroxide (if your pond bottom is not clean!).

Hydrogen peroxide temporarily lowers ORP to around 150-180 millivolts. I have learned to ignore that effect.

RE: Using Hydrogran Peroxide...


Wont work on pea soup algae; of the options out there, the two most appealing to me are 1) a heavily planted pond and 2) a UV light.

RE: Using Hydrogran Peroxide...

I have plants that are shading pond. I don't have a UV. Been thinking about one, but don't know how to install one. Yet.
Lisa, thanks for the info.

RE: Using Hydrogran Peroxide...


My first couple of years with my pond I tried to get by without a UV light because of there costs. I had many plants but my pond was in full sun all day and no matter what I did, my water always got to some level of cloudiness.

Once I bought a UV light, my water is crystal clear right to the bottom of the pond even during the hottest days. I would think a requirement is to make sure you get the correct size UV light for the volume of your pond.

Now, there are some negatives in my opinion. Forget the electrical cost (probably minimal anyway). The two issues I have is as the UV light kills off the algae, you will notice you need to clear off any filter mats if you have them quite often. In the heat of the summer, I have to clean my Savio filter media once a day.

The other issue is the crystal clear water will give any preditor flying over a "bird's eye view" of a feast down below. When I am on the second story of my house and look out the window at my pond, you can see every fish very easily so be prepared to protect them from preditors.


RE: Using Hydrogran Peroxide...

I have the same situation of full sun all day and the water is so murky that I can barely see the fish at more than 6 inches deep. (Pond is only 2 feet.) My problem is I need a UV that is simple to install as I am not very mechanically inclined, especially when it includes electricity.

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