Coral Bleaching

[Sam Samy]

DJ88,
Sorry I have'nt replied to your questions and suggestions. (Took the wife to Miami, Southbeach for a few days - does my eyes hurt from looking at beautiful woman and fast cars. Wife was not to impressed, but she was ammused with the male models walking around.)

Anyways, when I came back I found another purple acro that I just purchased from local supplier before my trip, start to bleach on me...

Here are my tank specs:
90 Gallon Tank
1.023 Salinity
8.1 - 8.3 PH
Temp. 78-80 degrees
A/N/N/P - 0
Calcuim - 470ppm
dKH - 10
Water movement by 4 returns and 3 power heads on a wavemaker powerbar. I do not have direct flow on my corals.

Now, I have another green Acro that is doing fine under these conditions. I'm thinking that the new corals that I have purchased ($$$) are getting shocked in my tank because of the 400W MH light. I have created 2 ledges about 12" below the MH bulb where I've been putting the corals on - could this be the cause.

I'm thinking that I need to buy some frags and try them in different locations of the tank before I find the Optimal position and process acclimating the new corals.

Any more suggestions from the experts???

PS - does anyone have frags that they want to sell - I need them to do tests within my tank????