I've got two locking-lid sterlite tubs, prolly a bit larger than they should be, but nevertheless, each one contains a BP, a juvenile, and another a full grown adult about 4.5" feet long.

I bought these a while back:

http://www.petco.com/product/6353/Zo...k-Heaters.aspx

for the large 50-60gal aquariums (24 watts). They fit fine on the bottom, and their each connected to their own independent Reptitherm 500r thermostat.

I use a hafl inc rubber feet to keep them up off the table they are sitting on, with cermaic tile under enath the tank.

Everything was fine for a while, except now they are failing left and right. I've replace them twice on each tank within a months time, each time i pull them off, it looks like little parts of the pad "melted" here and there.

I also noticed when the pad is on, the bottom of the sterilite tub seems to bow, of course due to heat. Both thermostats never seem to kick on and off, they just seem to stay on contstantly... average house temp is 72 farenheit, and their average temps are 81-83.

Am I doing something wrong here? Using to big of UTH's? Dont want to set anything ablaze, but this would be my 4th exchange of one of the zoomed pads within a 2 month time period.