What's the usual cause of this with sps?

[Biff0rz]

I'm so beyond frustrated at this point. This has been happening to every one of my sps corals and I cannot figure it out (montis, digis, acros). They all have been fine for months going through coral qt and even into the display. But as of late they all start growing this brown crud on the tip or top (Monti) eventually bleach/die. I started a thread about nitrates in a different sub forum which hasn't lead anywhere, and those are under control now (was 25-40). Po4 is a little elevated (0.14) but alk(8), CA(450), mg(1400) has been consistent. I've dipped corals only to be a pod mass murderer, no bugs or pests. I've checked par a bagillion times. In general, what causes sps acros to do this? I'm at a loss of what to do. This one just started this today, death will come soon, I'm sure.

 

[Charlie’s Frags]

Looks like your Copper band and Angel fish are munching on your sps

 

[Biff0rz]

Looks like your Copper band and Angel fish are munching on your sps

I can say with all certainty the CBB doesn't touch corals...snails on the other hand, haha. The potters has picked at some but not any acros. I verified this by watching a week-long video I took. Also, this happened to one of my acro's before that fish was added...so while the potters has picked on a few, those are actually doing ok. At the same time, I'm willing to move him to a different tank if I have to, but I truly don't think he's the cause.

 

[kingjames_dc5]

Looks like your Copper band and Angel fish are munching on your sps

When the light go out on the reef you’d be surprised what goes on lol.

 

[Biff0rz]

When the light go out on the reef you’d be surprised what goes on lol.

It's dino's