Hi.
Depends on what Algae you have but the basics stays the same.
You running at 2.8 WPG on your tank so you would need C02 to balance or doze liquid carbon source.Could be your problem?
Also what is your fish/bio load?To much nutrients in teh water like nitrate caused by nitrogen cycle when fish poop and plant material rots.To much nutrients and algae will rule.
I suggest if you dont have C02 already start to use it. DIY will be fine.
Then also if you have a hight bioload try looking into upgrading ilter if nto big enouth or simply just do bigger more often water changes.
