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Nasty green water

25 9:55:35

Question
I have about a 300 gallon pond( 7x4 and about 20" deep). I went and bought feeder fish cause I was told that an Eco system was needed to build up before I put any koi in. Well its been about 3 weeks and I still have most of the feeder fish and 2 koi, problem is the water is nasty nasty green. I have to clean my pump filter every day. How can I clear the water up to that i can enjoy my fish pond? I also have 2 plants in the pond as well

Answer
I'm sorry about your problems.  Algae is to be expected in a new pond and normal.  My page on controlling algae is at http://www.fishpondinfo.com/plants/algae2.htm
The main things are few fish, good filtration, lots of plants, good bacteria, and maybe some barley straw.

You should not be cleaning your filter every day.  If you are, the filter is not strong enough or the intake has too small a surface area.  You can increase the surface area by wrapping the pump in filter material and setting that into a plant basket with holes.  What kind of pump and filter do you have?

Koi experts say to have 1000 gallons for the first koi and 100 gallons for each additional koi minimal so your pond is kind of small for koi, at least the adults.  I would stick with the two koi you have and maybe get some more goldfish once the pond is under control as far as the algae goes.

You should add a lot more plants to your pond, improve your filter or get a bigger one, add good bacteria like Microbe-Lift, and hopefully things will improve.  Read over my algae page.

Good luck!