Only monti caps survive

[Das awesome]

Hey guys,
I'm not sure which forum to put this in, but just recently I got an ecoray par38 bulb for my biocube 14g. The guy at the lfs told me that I would be able to keep sps with this bulb, but so far, only monti caps are thriving. Any other type of sps I keep slowly loses it's colors and dies. I have the bulb pretty far from the tank, almost 2 feet above b/c that's the only way I could get the light to cover the entire tank. I do once, sometimes twice a week water changes. Nitrates are undetectable, alk is at 10dKH and calcium is around 420.

How come I can't keep any sps alive besides monti caps?

 

[KeithB]

You need to get it closer to the tank. That light relies on its lense (it has a tight focus) to deliver its limited (15w) output to a small area in order to provide enough light for growth. By placing it so high up to cover your tank, you're defeating the purpose of the tightly focus and consequently delivering very diffused light to your tank. I believe its specs are 250 par at 20 inches. That's fairly low for SPS.

If you really want to keep SPS, I'd suggest buying another one and keep them both at ~10 inches over the tank.

 

[Das awesome]

Thanks. When I had it lower, just the center would be lit and the sides would be extremely dark. Looks like I gotta go get another one then

 

[KeithB]

I love this hobby! Never a time where you don't need to spend $$$.