Coral dying rapidly, please help!

[samnaz]

My octospawn is falling apart and dying very quickly. I added it to my tank 6 days ago and up until this evening it seemed healthy.

I need to do a water change ASAP. I made a 7 gal batch of Reef Crystals, with a 1000gph powerhead, when is the SOONEST I can use the freshly mixed sw?

Two days ago:

Now:

 

[samnaz]

HELP pls anyone? I can't lose this guy.

 

[Tautog]

Wait to water to clear, usually within 15-20 mins, but do a 50% WC
As long as temperatures match or close, and salinity too WC immediately
Looks bad

 

[sebastiaan1985]

while mixing the fresh water, check all parameters.
What type of flow and lighting was this frag in at LFS and what is it in now?

 

[ebushrow]

tank age, parameters, filtration, lighting?