I've had cyano for a few months now and getting very tired of it. Consistently have 0 nitrate/phos with Hanna checker and Nyos test kits. Been dosing NeoNitrate and Microbacter7 daily for the past week to try to raise and it wont budge, so am about to start dosing phos as well. I'm up to 6ml NeoPhos which is higher than what the bottle says for my 32g tank. Do I need to stop skimmer entirely for a while? I've stopped water changes for a while now, have been siphoning cyano weekly, filtering the water through coffee filters, then returning same water to the tank. Is the skimmer just that effective or what am I missing? Also having a hard time understanding the relationship between nitrate and phos, so can someone explain the biochem?
Neonitrate and neophosphate are fairly weak products that are expensive and lack a purity guarantee. When you need to boost N or P, my opinion is that food grades of ammonium bicarbonate, sodium nitrate, sodium phosphate (of various forms), and calcium nitrate are all better bets.
As the to cyano and the current nutrient levels, cyano, being a bacteria, can thrive on organics and may use N and P from the water as it grows. Thus, it may be the cyano that are dragging down N and P.
Short of antibiotics, treatments for cyano often include reduced organics in the water, more flow, and manual removal. While boosting the N and P is good for preventing dinos, it won't readily reduce the cyano. Stopping the skimmer would be counterproductive since it will raise organics.
That all said, are you sure the problem is cyano and not dinos?