Halide over oceanic center brace

[shumoco]

I just closed a deal for a nice light fixture. It has 3 single ended, 250 watt 14K's, and two 5 foot T5's for actinic suplimentation.

I've never had halide's before and am concerned because I have a 12" wide glass center brace on my 60" oceanic tank.

My question is, "Can I use the center 250 that will be over the brace without the brace cracking?" "If so, how high should I keep it above the brace? Or should I just fire it up and keep checking the temp of the brace?"

I've seen so many horror stories of braces cracking from the heat of halides, quickly followed by catastrophic tank failures, that I'm a little scared. I can't remember if they were all acrylic or if some were glass.

What have you guys experienced with this?

 

[Runfrumu]

I have my 3 150's over a 72" and the glass on the brace is never hot, just mildly warm, as in not much warmer than anything else on the tank. The are maybe 9-10 inches from the glass.

 

[shumoco]

Thanks, runfrumu, that's good news.

Man 9 to 10 inches is high, my T5's are about 3" off the water. This should make working on the tank much easier.

 

[Dubin]

I run 3 250w SE Radiums over my 180g oceanic and the glass is fine. I also have my light 10" off the water though, and like Runfrumu said, the glass brace just gets a little hot.

 

[jjk_reef00]

With the mh you are going to want to place them much higher than t5's because of the heat (transmitted to the water let alone your brace). Try at 10" and gradually lower it if you feel you need to. Also watch your water temp if you are not running a chiller. When I first switched to mh I almost cooked my tank 85 or 86 degrees because I didn't use a fan, had the light 5" off the water and the house was at 80 degrees (in AZ). Good thing it was just a 29 gallon cube with softeys. I raised the light and added fans and then it was fine.