In my experience, it depends on the type of heater. I have had the cheap glass ones that sometimes got very hot, and did burn. I now have the Marineland Stealth and that one is great. Not hot to the touch, won't shatter, and is fully submersible. The only problem is that there isn't a light to tell that it is working.
cheers for that guys ,thats good to hear, i.m not sure what types mine are, silly me through away the boxes, but they were epencesive,even for the smaller ones,any way the good news is the fish arn,t stupid.
I think they're just close by it for the warmth, and maybe your clown's are cold . Anyway, i sometimes worry about that too, but the fish seem unharmed and i trust their instincts more than mine (except with food) .
__________________ 10 gallon: Female Cambodian Betta, 2 cories 20 gallon: planning to put some livebearers Outside Pond: empty for the winter
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