Put your light on a Timer 4 hours on MAX, than off for an hour or so, than back on again.... The trick here is to never leave your lights on more than 4 hours.
Algae is not very good at photosynthesis not like plants are. Plants will Start converting Light energy the second the lights turn on, algae needs 4hours of steady light before it starts the photosynthesis process, Once it starts tho it is a very fast grower,
A very experienced person told me this years ago, and I have never had an algae problem since.
He runs his system (heavily planted) lights on 3 hours off 1, on again 3 hours off for one, and over and over again. there is ZERO algae in his tank