Lighting Help - Deep Blue 60 Frag (48x24x12)

[jpkrze]

I recently setup a 48 L x 24W x 12H, bare bottom display tank with a lot of rock that goes up to 2" under the water. Im using an 24 inch 8 bulb ATI Sunpower fixture from my old 30x30x18 cube and it actually lights the entire tank. I have a lot of LPS / acans on the bottom and those are doing excellent. However, any SPS I try to add die a long slow death. My old cube tank grew SPS like weeds with the same equipment. Fixture is at 20" above the water line. Trying to figure out what I need to do...

 

[YoungREEFA]

Borrow a par meter, that will answer your question

 

[that Fish Guy]

Maybe you need more Flow.

 

[kellerexpress]

I suspect you have too much par with the shallow tank

 

[Michigan Mike]

Proper placement of corals should be fine, as you said they grew fine before.
Keep SPS directly under the reflectors/bulbs and acans on the outskirts.
I think 20" above the waterline is overkill.

In all honesty you could use another 24" fixture or longer tubes. The light on the far ends of the tank may look lit up but there is very little light beyond the fixture's sides.

Got a pic? Sounds like a interesting rockscape.

 

[jpkrze]

Unfortunately I don't know anyone with a PAR meter. Regards to flow- tank definitely has plenty of mixed/random current. The SPS would be centered under the fixture and everything else is off to the left and right. Will try to upload a pic. Any idea how much PAR this 8 bulb ATI puts out? And PAR isnt really lost through air right? It's really effected by water depth though. Considering the tank is only 12" deep Im guessing that my PAR numbers might be extreme.

 

[jpkrze]

Any other opinions?