Two Questions?

[beapeams]

I have a glass tank 120 gallons 5ft long 2feet deep. It has a plastic brace where the glass covers sit. Is there any issues with removing or cutting that down, one of my Metal Halides is being blocked by the brace. Also, I have a 3 x 250 + 2 x 150 MH fixture, and it is positioned 9 inches above the tank, should they be higher or lower.

Thx

 

[thatguy]

If you mean the brace in the middle, I would strongly suggest against it. That is there to keep the glass from bowing out, or at least help reduce it. I think you would be much more likely to have a blowout without the brace but I could be wrong. Some people have replaced theirs with pieces of glass or acrylic. Someone else would have to give you more info on that.

If you aren't talking about the center brace, just ignore me.

 

[Hobbes8017]

You have 5 MH bulbs over your tank, there is no way I would chance taking out a brach just to reduce alittle blockage of 1 bulb. The brace is probably not blocking 100% of the bulb. So you are getting plenty of light around that brace.


I could not tell you about how high to have your light fixture. If you think about some of the LFS, their lights are pretty high off the surface. My bulbs are currently 7 inches from the surface, but they will be higher with the new canopy. I have a fear of a fish splashing them and watching them pop from the cold water!

 

[DrBDC]

6-9 inches is the norm on height. Most bulb measurements are done at 6,9, and 12. There are only a couple type reflectors that are even worth a darn at the 12" level. The intensity and focus becomes almost worthless. T5's are usually measured at 4 inches above the water line.

Is the brace a really wide one? If the tank is empty, some will take a strip of clear acrylic with enough width and thickness to be strong, cut the center brace off leaving enough to get some good bolts on each end, then glue AND bolt the acrylic to the remaining part of the cross brace. Don't do it full.

With light coming from 5 sources I wouldn't think the stock bracing would create a shadow though.

 

[beapeams]

That is the funny think the brace is not wide, but when the 150's are off there is a definite shadow in the middle of the tank. I was thinking about having periods where the 150's would be off, just for heat in the room, I have a chiller so the tank temp is not an issue. I guess I will leave it, the tank has been running for a year and 4 months now and draining it to change the brace is not an option. I have to change a ceiling mount for the light which will change the position of the center light, I will try to adjust it then to see if I can get less of a shadow.