"Waterflea" Filter Clears a Green Algae "Pea Soup" Fishpond

Hi, I have a tiny fishpond with a few goldfish and since about a week after putting them in the water turned green and I never saw them again except at feeding time. I tried all sorts of solutions but every one of them failed. This year I used a 1.3 rain barrel as an upper (fish free) chamber and a little airlift pump to move water up to it, to let the big crud settle. It did not work great. However I added a few waterfleas. About 3 weeks later the water was clear! It seems that the waterfleas have gobbled up all the green soup and now they are not only acting as a cheap filter but also occasionally dropping through the outlet and becoming fish food. I don't know if other people have done this or how long it will last or how big a water area it can clear but it may be of interest to some of you. I hope so. I read up after doing this and found out that some commercial growers of waterfleas (as tropical fish fishfood) actually keep goldfish so they have a supply of green water as waterflea food! Not sure why they did not just link the 2 systems. Anyway here is a link to the video. You can see the waterfleas in the video. They are daphnia or a close relative. I got them from a local pond. https://www.youtube.com/watch?v=VW4ppD2MErI