I use snails and tilapia, shade will help as well, the shade can be in the form of water plants works, but it might take a while to figure out how much surface needs to be covered. I have an 8x12 pond that needed 50 to 60 % coverage, so I added snails and the tilipia, which was a stroke of luck. Spider mites wiped out almost all of the plants.
I have about 10% coverage now, but the fish and snails are keeping the algae at bay. I don't know if tilapia are legal where you are, but you might try an aquaculture supplier, they will be all male fish, but if your goal is algae control and not forage they might work.
