Reptile & Amphibian Forums

hello all. I've built a rack out of 3/4 Melamine that is 2'deep x 4'wide x 6'tall.this rack holds 27 32q tubs. I'm using 4 6 foot strips of 11"flexwatt that run from the bottom to the top as back heat. I left the bottom shlef empty for storage & also because I don't think that shelf will really stay warm enough being so close to the ground. my problem is that the bottom (actualy the 2nd shelf)only gets to about 81 degrees while the top is at 90 degrees. I bought weather stripping & put that on the back of each shelf to try to cut down on the heat rising & it helped a little but I need advice on evenning out the temps. was also wonderring if the flexwatt had a tendency to run hotter at the end of the strip perhaps. just a guess. thanx in advance for your help.

Your problem is common with back heat perhaps you should switch the tape from running vertical to running horizontal so that each strip may be adjusted accordingly. Alsdo heat doesn't rise that is a big misconception hot air rises, thus the top rack is often and very typically 10* warmer than those on the bottom. In my cage set ups I dal the bottom rack or cage up a bit from norm and dial the top down. It takes time and requires constent attention, but it works.

There are other ways to adjust your rack. Such as creating vent towards the top to let excess hot air escape. Than you could dial up the heat and produce a better gradient at the bottom. i imagine if you dialed it up now you would get 100* tubs at the top little to warm.

Also the tape runs constent from each end to the other I find no warm spots along the length. It is pretty trust worthy for what it is. So no there is not a warm or cool end.

Best of Luck

>>hello all. I've built a rack out of 3/4 Melamine that is 2'deep x 4'wide x 6'tall.this rack holds 27 32q tubs. I'm using 4 6 foot strips of 11"flexwatt that run from the bottom to the top as back heat. I left the bottom shlef empty for storage & also because I don't think that shelf will really stay warm enough being so close to the ground. my problem is that the bottom (actualy the 2nd shelf)only gets to about 81 degrees while the top is at 90 degrees. I bought weather stripping & put that on the back of each shelf to try to cut down on the heat rising & it helped a little but I need advice on evenning out the temps. was also wonderring if the flexwatt had a tendency to run hotter at the end of the strip perhaps. just a guess. thanx in advance for your help.
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Jeremy

"I am become death, the destroyer of worlds" July 16, 1945 Robert Oppenheimer

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1.1 Hypomelenistic RTB's
0.2 Pastel Hypo RTB's
2.0 Double Het Stripe Albino RTB's
0.1 Suriname RTB
0.1 Anerthrystic RTB
0.0.10 Red Bearded Dragons
1.1 Rhinoceros Iguana's
1.0 Green Iguana
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I agree with bighurt. This is one of the problems with back heat and why I don't like to use it. Flexwatt runs the same from end to end. Lower shelves run at a lower temp and overall, you lose heat out the back. The best solution would be to reinstall the tape as belly heat. A separate dimmer per shelf would be nice but you could probably run the lowest two shelves on the same dimmer. Since you have nothing to lose at this point, I would try the following. Run over to Lowes or Home Depot and get some 1 inch thick rigid insulation or reflectix. Secure it to the back of the rack over the lowest two heated shelves. This prevents back heat from escaping out the back of the rack. It pushes the heat forward. This should raise the temps of the lower shelves. It may even out the temps with the upper shelves. It would be a lot easier than removing the back heat and converting it to belly heat.
This worked with my first and only back heated racks. My evening temp drops were dialed at 10 degrees but the racks were dropping a full 20 degrees. When the room was coldest, the racks were not getting up to temp during the day. 2 inch rigid insulation on the back and sides that faced a patio door resolved the problem.
Best of luck

When I was breeding rosies, all of my females on the lower levels would always breed late or sometimes not at all because the temps were so much lower on the lowest levels of the rack.

Heat cable is great because you can run more cable down low, less cable up high and get even temps when running the entire rack off a single thermostat.