On 2005-05-03, sophiefishstuff
wrote:
If the weather is warmer (and I have to say it is not for many days a
year that the ambient temp. is close what I want the tank to be) won't
the heater just switch itself off?

I'm too newbie to properly answer the question about the 8C temperature
difference, but he was referring to what happens when (it's my
understanding that it's a "when" and not an "if") the heater fails. If
it's a standard analog heater, it will probably get stuck in the on
position, and a smaller heater will likely cause less damage to your
fish. If, on the other hand, it's a digital heater, it will probably
fail in the off position, causing a somewhat less dangerous (but still
serious) situation.

NetMax has a great explanation on his site he
http://www.2cah.com/netmax/basics/heaters/heaters.shtml

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