Keep loosing Sailfins, and only Sailfins

[RickNavyDad]

So I have a new 40 breeder, but up about 5 months. Tank is still going through it's stages. Seems to be getting past diatoms, still getting them during the day and recedes at night. The cleaning crew is making progress on it, and I seem to be getting some green algae as well as coralline algae on the rocks. So before I added the tang, I had and still do, 2 cardinals, a chromis, a goby, pistol shrimp, snails, and hermits. Everyone was doing great. I added the tang, a very small Sailfin, did ok for the first 2 weeks. It ate but nothing crazy, didn't pick at the rocks much, ate mysis, and never would eat the seaweed sheets. One day I see the tang not doing well, won't eat, next day dead. No signs of disease and pretty much gone over night. Water by my testing and LFS good. LFS replaced the tang that was eating at the store, and put him in Friday. It did good Friday ate, swam around, picked at the rock, and looked fine. Saturday, hiding won't eat and this morning dead. Nothing else is dying, fish, inverts, coral frags. So by my testing, 1.025 salinity, Ammonia 0, Nitrate 0, Nitrite 0, Phosphate 0 (yes I know there is an issue in that), and ph 8.0. All but the phosphate were with red sea test kit, and the phos with API. What could be in the water that the tang is so sensitive too. The waters been cloudy but not bad, assuming it is a bacterial bloom. Any thoughts and ideas are appreciated.

 

[9975]

Bacterial blooms can suck the oxygen out of the water extremely quick but that would affect all of your fish.

Personally I would give up on the sailfin as it will outgrow a 40 breeder before you blink twice