Algae grows from only one thing, build up of organic nutrients, usually from feeding. Cyano
can be triggered by high silicates as well. Some salt mixes are high in selenium.
Your plants exist on very low levels of nutrients, so you can have high phosphates (over .1ppm IMO
) and also a lot of plants. My nitrites for example just .018 ppm
and my plants still grow . Algae is very good about locking up nitrogen byproducts. I agree with comments that consistent water changes, change in feeding habits and physically removing what algae you can will set you right. My algae in my scrubber starts slowing down when I get phosphates below .1 ppm
Everybody has an opinion on any of these forums . As with any information gleaned from the Internet, you have to eventually make up your own mind as to who is right. Sometimes what gets posted is a bit more aggressive than it needs to be. When I had my fish stores, experts walked in every day with one sort of nonsense or another. I just smiled and nodded.