Thanks mate, it's a pleasure.
Most likely the bacterial infections are just general instability in the system, fluctuating nutrient profiles, flow pattern changes and lighting. Everytime I've changed my nutrient management my tank has had a bacterial bloom of some kind.
Zoas will release nutrients and amino acid from their flesh when there is a change in the waters nutrient profile or lighting. It's a way of self regulating but the bacteria take advantage. Iodine dips seem best suited to clearing the bacteria on the flesh of the polyps as they are mild on the Zoa and do kill that bacteria, just dip and blow off the bacteria a few days later, dettol/coral RX works well also and is the champion all in 1 Zoa dip IMO for pests and bacteria.
It's hard to keep things the same as sometimes things happen that cause changes inadverantly. Power heads clogging, bulbs shifting spectrum, reactor failure, RODI fouling.
Since quitting skimming and focusing on just phosphate removal my zoas seem to be a bit more resistant to other parameter fluctuations. They're also growing steadily.
That said I will be switching over to an algae scrubber which will keep my phosphate at 0.03 and nitrate at about 0.75ppm. It will be a bit lower than I prefer nitrate to be but it will be stable with no phos spikes from old rowa media.
