STN? or bad luck?

[brettz16]

Its been a while since i posted and unfortunely have to come back with this thread. I have had a couple sps die in the last couple weeks which i think might be from STN. The only thing i have changed since my set up was salt( i went from IO to Oceanic). It started about 4 months ago when i think i stressed out a large colony of birdsnest. It bleached or STN until i finally fragged and tossed it. Since then all the frags of it died. Time went on and i collected alot more sps. Everything was doing great for about 2 months until i started seeing it again on some of the frags. Its starts with a random part of the coral turning white and loosing flesh, then the enitre coral doesnt extend the polyps.

I also lost two fish: A anthias which i still have yet to find, i checked every possible spot in and out of the tank. And then my fav: the potter angel. He was fine the one day, the next had a white film over his scales and died the next mourning.

I recently did a 60% WC

I have other sps like digi's and stylo's and soft corals and clams there are doing great and even showing greater growth then before.

I just checked my parameters as i have been doing just about every other day:
temp: 78.5 (RKL)
PH 8.1 - 7.95(rkl)
Nitrate: 0.2 (RS and salifert)
PO: 0 (salifert)
Alk 9.0 (Salifert)
Mag 1700 (RS)
Cal 500 (salifert)

I run BRS carbon and GFO, 15% bi-weekly WC's, 15ml vinegar daily


please help

 

[poidog]

You are dosing a carbon source, so are you supplementing with amino acids for the acros? I stopped dosing carbon... acros hated it. I had much happier, healthy, and colorful acros with a nitrate of 20 then I did with an ULNS.