Some more info about your tank and its occupants will be helpful.
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So it’s a 120gal mixed reef setup with a sump refugium, nitrates hold steady around .5ppm & phosphates .05ppm, temperature is steady between 77.8 & 78.1 the tank is 3.5 years old.
The last fish I added were 8 months ago- helfrichi firefish, copperband butterfly, anthais trio. Other than that I have a blue spot goby, a pair of Wyoming white clowns, a trio of pajama cardinals, a pair of green chromis, a green mandarin, and a spotted crouching goby.
I have a bubble magus auto dosing system with calcium alkalinity mag, coral amino, tropic Marin trace, and I run a small amount of bacto balance.
I run a ATO with Rodi water that keeps my salinity pretty well constant at 1.025.
i feed a 1/4 sheet of nori a couple times a week, and feed spirulina enriched mysis as well as PE mysis shrimp. I typically feed 4 cubes (2 of each) once a day or twice a day when I have the day off.
it has also probably been almost a year since I have added any coral. My fish additions last September were the final livestock purchase I made.
I appreciate everyone’s insight!