I have been battling algae in my tank I set up recently and have gotten some good advice which I'll share. If you don't have a rodi
get one, the extra nutrients in tap water is like steroids to algae. Also if you don't have one get a skimmer, it strips excess nutrients from the water. Having some carbon is also helpful, depending on your setup you can add it to a filter or anywhere else that water will circulate around and through it. GFO
is also really good to use as it strips all the nitrate and phosphate from the water (this is what feeds the algae) another consideration is the amount of time the lights are on and if the tank gets any sunlight, once nitrates and phosphates are removed it eliminates the lighting issue though. Also watch your feeding because overfeeding puts the nutrients right back in the water. Another thing to consider is either a refugium or algae turf scrubber. Both systems give algae a protected place to grow and strip the nutrients from your water that is out of sight. Algae is helpful in an aquarium it just looks like crap.