I also live in Texas and with our hot and dry spring, ponding has been a challenge this year for sure.

My 8' tank has been clearer than ever this year, but the tanks without pumps/filters are green/brown.

Hang in there

Mine wouldn't clear up at all until I added a bunch of plants - then it cleared up in 2 days!!! Maybe add more plants? I know it's tricky with koi though.

We are always in the 90's all summer and my 3+ years have been fine with clear water always. I have mentioned my stream (loaded with plants) several times here. I realize it wouldn't work immediate miricles to put one in, because there wouldn't be established root systems, but I believe they are my entire filter system since essentially ALL I have is a pump and stream. I don't have uv, batting or pump prefilter, or skimmer. When I have had to look into my skippy, it has been completely clean.

Admittedly, I have the equivelent of 30' of stream, but I suspect even a few feet would do the trick.

Have you checked the bulb on your UV? They only last one season.

Is there someplace you can get a load of water hyacinth? They are terrific at straining out excess nutrients, plus they cover the pond's surface, reducing the amount of sunlight below.

If the koi eat your hyacinth roots, try putting them in the skippy. I've seen hyacinth in filter boxes grow to huge sizes. Is there a way you can add shade to the pond, like with a picnic tent?

Thanks for the replys, uv bulb is new,guess it could be bad.The skippy is full of water hyacinth, I pulled some out yesterday and put in pond. I also have 2 water lilys that are 2 yrs. old but doing OK. As this is a stock tank 6' a stream not really practical. I have rigged a shade cloth that cuts the worst of afternoon sun from tank. Maybe 100+ temps. just give this result. Has anyone used products to adjust PH down?

Messing with ph can have disastrous results for your fish.

I'd say the problem is heat and sun and your additional plants and shade will do the trick.

I agree with buyorsell888. Don't do too much stressing about the ph. Mine tends to run high as well.

You said you have an UV but you didn't tell us what is important such as what make or model. Also tell us the flow rate thru the UV? What is the size of the stock tank? How large is the two Koi? What is the PH of the pond water? What is the PH of the tap water after it sits 24 hours. Is the water from a well? What is the temperature of the water?
Mike

I will try to answer the questions on the last post. the UV is a 10watt pondmaster, the pump is 800gph or close,tuned down by 1/4. the stock tank holds 636gal. if my math is correct. 6ft.rnd by 3ft deep. The Koi are 16" and 10" also 2 goldfish about 6" Pond PH reads 9+ on wide range liq. test kit. water is from city(small city on well)in drought. and reads 7.5 after 24 hr. Water is warm(it wouldn't make a refreshing dip. but thermometer is full of algae so unreadable. air temp. around 102. So should I worry about the PH?

If you have a good bio-filter large enough for the size of your pond and the fish in it, you will never have to use barley straw or u.v. lights to keep your water clear of hair algae and suspended algae and your fish will always be healthy. I've got a great diagram and step by step pictures of a bio-filter we've been using for years to keep our ponds clear if anyone is interested.

Your's Koily, Lorraine

Clear water is best achieved with a multi-pronged approach. A UV light is a fantastic and effective aid for getting rid of pea soup. It works magnificently by itself, but in combination with water lettuce and hyacinths your water will be crystal clear no matter how much sun you are getting. My pond is full sun all the time and it is nearly always clear to clearish. A third pea soup countermeasure is water lilys which limit sunlight. They also look beautiful, especially tropicals. Once a year I make a pilgrimage to a local nursery and stock up on tropical water lilys of all different colors, both day blooming and night blooming with gorgeous green, maroon, and variegated lily pads. I also pick up a Victoria lily which has 4 foot lily pads that provide lots of cover from the sun, as well as a place for the frogs to sun themselves. The nursery starts growing them in the winter so by the time I pick mine up, it is already generating 2-3 foot pads. I stay away from barley straw and/or concentrate because while it is effective in limiting string algae, it also prevents my pond liner from achieveing a coating of algae for my fish to graze on. If your fish do not have algae to graze on constantly, they might take a second look at your lilies. I have 30 koi in my pond and they do not touch the lilies or other plants because they have plenty of algae in addition to my frequent koi food feeding schedule.

So to eradicate pea soup, here is the list in order of importance:

1) UV light (overengineered, get a big one that is designed to sterilize a pond 2-3 times as big as the pond you have. I use a 160 watt Aqua UV even though my pond is smallish (4,000 gallons).

2) Nutrient sucking filter plants like water lettuce and water hyacinth. I keep mine confined in a screened circle because I do not want them to get sucked into the skimmer)

3) Solar-limiting water lilies.

No, don't worry about the ph. You need to shade the pond either with plants or other means to cut the sunlight to reduce the algae growth.

Just another thought.

Your fish and plants have surely grown in the last four years. Have you increased the size of your filter? I have to make a bigger and bigger filter every year. If I make them easy to clean, I will do it more often.

I think everybody has string algaw in this heat also.

thanks everyone for the input. I may have turned a corner(fingers crossed)string algae is down,water pretty clear, at least I can see the fish in the 1st 2 ft. I think I will not stress over fish ph stress, I hate to add chem. if I can avoid it. I may have to make a bigger skippy filter as "Frankie" my 16" koi seems big for my little tank but have grown fond of him. Sometime I heard that they stop growing if they pond is to small for them. Fact or Fiction?

Fiction

Koi can become stunted or not develop properly in ponds that are too small and especially too shallow but they don't stop growing to fit small ponds.

They can also die easily if water quality isn't perfect or oxygen becomes too low, the bigger they are the easier they will die.

It is very easy to get attached to them and giving them away or building a bigger pond isn't always practical.