Cannot get rid of cyano!

[dc4]

Marko, try dosing vodka, ever since I started with vodka its has helped control the excess nutrients in my tank. I only do a water change when I clean out my sump and thats only once every 2-3 months though I do add 5g of ro a week due to evaporation but everything in my tank is doing great. I also overfeed my tank at least twice a day but my tests always come out zeros.