Re: [APD] Remove center brace from 75-gallon

["Eric Wahlig" <ewahlig at earthlink_net>]

I (maybe wrongly) assumed the brace was made of glass, maybe its part of
the molded top frame (plastic) or if its an acrylic tank, then part of the
top plate. I don't know, or can't remember, what kind of tank Adam said he
had but he did say he was interested in setting up an open-top style tank.
In this case, I think if you set up the lights and monitor the temperature
you'll be OK.

Louis points out "Careful with MH over the center brace.  Bad things can
happen" and links to an article documenting a disaster. In looking at the
photos, I can see that the lamps were very close to the top of the tank.
The author says they were 5.5 inches above the top and needed to rely on
fans to keep them from causing damage. Of course, as Murphy's law would
have it, the fans did not turn on as expected and the 400W MH lamps cooked
the acrylic. If you keep the lamps far away from the tank, like 1.5 feet,
then I think you won't have to rely on fans to protect the integrity of the
tank but you may still need a fan to cool the light system itself. The
light setup that Adam has may already have a fan or two in it. I think most
of the commercial ones do. Personally, If I build a light system, I
hard-wire the fans to the light circuit so they have to run if the lights
are on. No plugs or timers on these.

The other point I make is just common sense. No matter what, don't just
plug everything in and leave for a long period of time (such as the author
of the disaster article did). Set up the system on a day that you can
monitor it. Then, after your 'e satisfied that everything is OK and the
house won't burn down, simulate potential problem spots like unplugging the
fans, or whatever else might cause a disaster if it stopped working, and
monitor these effects as well. Then you can be reasonably sure that no
equipment malfunctions are going to cause a major disaster, although the
occupants of the tank might be adversely affected. A relatively small
disaster in comparison.

Back to the brace again: If its the molded plastic kind (part of the top
frame and probably a dark brown or black color) plastic then I'd consult
the tank manufacturer about any material degradation over time from the
strong lighting. Maybe a shield on this kind of brace is a good idea. 



--- Eric



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