You could try some phosphate remover, and monitor your feeding, sometimes its your lighting that promotes die off or growth, changes in photo period, different bulbs, bad bulbs. If you can keep a good flow over everything, and prevent dead spots for where waste usually hides, its a big plus. I would try not to have any waste, do water changes with RO/DI or RO water, feed only what fish eat.
I went to a lecture this year and was told that one algae competes against another, so you could do a fuge with as many algaes as possible. Algae is a perfect exporter of phosphates. Phosphates being a source of food for your Algae.