Need help - can't seem to keep LPS, softies are fine

[Cary Meredith]

Ok, So here is the situation tanks about 15 years old, using RO, and everything is testing perfect, I can't seem to keep LPS but some seem ok, can't figure it out what could be going wrong. Last year I tried some acans and kept them maybe 3 weeks and started to die back. Now this year I have been doing zoas and softies, everything pretty much is doing great but then got a couple of other lps, a hammer, a frogspawn, all either getting pale or receding. Also got a chalice and placed in tank and overnight the flesh receded.

Really need to figure this out.

Thanks
Cary

 

[Reefing Madness]

Gotta have those tank numbers. Remember that Softies are bullet proof, LPS require some maintenance. Also, whats your TDS?