Just a thought, I hope it is not tooo radical. If folk try to 'push' the fish numbers and size up, by stocking lots of fish, and feeding them perhaps a bit on the heavy side, is it any surprise the algae and the aquatic plants are going to be the main recipient of all the 'trickle down' of fertile stuff going into the pond?

I couldn't imagine a better way to encourage the green stuff, then feeding fish heavily.

If you want to reduce the plant growth, perhaps culling fish and cutting down fertile 'inputs' would result in fewer, but bigger fish and clearer waters...

regards, andy
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