In article ,
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I just bought an Eclipse System 3 Aquarium. I am having trouble with it
~overheating. Thinking it was the lighting (6W NO haha), I left the
lighting off for a day (I don't have fish yet). The temperature did not
decline. In fact, it went up - from 81F to 83F. I am now quite certain
that the motor in the filter (35GPH) is heating it to this temperature. It
doesn't seem to me that such a small motor could do such a thing. Is this
normal? Has anyone else experienced this?


A defect in the motor windings could cause the power dissipation to go way up. It
is not an unusual fault, in general. Excessive friction in the rotor could also
cause excessive heating but to a lesser degree. You might take it apart to make
sure that it is assembled properly and that you don't see anything suspicious.

The best test would be to use a wattmeter and see how the power consumption
compares with the Marineland specs. Since you probably don't have a wattmeter,
perhaps you could try only running the pump for a minute or two every half hour. I
think that would be sufficient to keep the biowheel vital, but the motor heating
would be chopped way down. Since the tank still has a lot of thermal capacity, it
will not lose heat that fast so you would have to keep up the experiment for
several hours, maybe half a day.

If you haven't called Marineland, that would be a good idea. Their technical
support is pretty good and they may know of some specific problems. You will
surely get it resolved between your experiments and their help.