Cyanobacteria

I'm giving up the fight against cyanobacteria. Two months that I can't get rid of them. I do partial water changes twice a week, blackout for 2 days, I stopped feeding for 1 week and adjusted the filter flow to the maximum. In addition to in the partial exchanges I vacuum all cyan together.

This aquarium has 30L, subulata, vallisnerias, cryptos, microsorium, 13-watt luminaire, fertile substrate and basalt.

Fish are Garra Panda, German Kaiser, female guppy.