By Request - green tank pics

[AJ_77]

Tony, the lights are 4 OVRNO (3 65k, 1 10k) on 2 of those e-ballasts, and 2 NO actinics. The 4 NO are new, the actinics are middle-aged or so. No sunlight at all hits the tank. The only thing that I can point to is my POS skimmer basically stopped doing anything for a few weeks before this started. Of course I got the new one pretty quickly (TF1000 Multi). It's been working hard since.

I've yet to implement new lighting over the refuge.

Darren, I top up daily with RO, but weekly changes are from the tap, and treated with the bottled goop from Big Al's for chlorine, etc. I have never used DT's.

Your solution seems very near to shutting the tank down. I have considered that.

Cheers, all.