I was in a similar situation - chasing low no3 and po4 ( as I knew from the past) using Nopox and po4 binders until my tank crashed - most corals died and in few days gha and cyano took over. Ugliest tank ever gha covered by cyano. Sand, rocks and even pumps covered by red slime. My panic thought was that I have too much nutrients, so increased nopox dosing, more po4 absorber and even a much bigger skimmer- just to make things even worst
This happened after 5 years in the hobby
Just before drying out my tank I decided to read and learn a bit more...
So my actions in last few months:
- stop any nopox, PO4 absorbers, etc
- increase feeding - still didn’t helped as had 0 & 0 even after weeks, but fishes happy
- started dosing NO3 - took some time, but now stable at 20
- started dosing PO4 - even 0,2 / day just to measure 0,01 next day. Still dosing it after couple of months (0,02/day) to keep it stable at around 0,04. Probably will go a bit higher soon (0,1)
- Things getting slowly better, but not great. Next step was dosing H2O2 to eradicate remaining cyano and gha.
My tank looks again great and lesson learned is I need both no3 and po4. Also most probably will keep the H2O2 dosing for long period
This happened after 5 years in the hobby
Just before drying out my tank I decided to read and learn a bit more...
So my actions in last few months:
- stop any nopox, PO4 absorbers, etc
- increase feeding - still didn’t helped as had 0 & 0 even after weeks, but fishes happy
- started dosing NO3 - took some time, but now stable at 20
- started dosing PO4 - even 0,2 / day just to measure 0,01 next day. Still dosing it after couple of months (0,02/day) to keep it stable at around 0,04. Probably will go a bit higher soon (0,1)
- Things getting slowly better, but not great. Next step was dosing H2O2 to eradicate remaining cyano and gha.
My tank looks again great and lesson learned is I need both no3 and po4. Also most probably will keep the H2O2 dosing for long period