Heat Transfer from equipment.

So today I was netting some fish in the shop and noticed that one tank was warmer than the other. So I pull out my trusty TDS meter with digital temp.

Tank with just a air driven sponge filter was 24.9 celcius. Tank with sponge filter and hang on back filter is 25.5 celcius. That means its 1.1 degrees warmer with the hang on back.

I'm assuming the motor of the hang on back filter is transfering heat into the water. My next test is going to be to remove the sponge filter in the tank with the hang on back and test the temperature vs a tank with a sponge filter only.

This might be useful when setting up a tank as learning that a hang on back filter on a 20 gallon tank may raise the temperature by 1 degree. Might not seem like a lot but 1 degree temp raising off 11 watts of energy for the hang on back is pretty efficient I think. Considering it's a byproduct of the filter, compared to a heater where all it does it heat water.

Also Cory, the smaller tanks, like the Evolve8's that I use, have the small submerged pump in the back section for filtration which raise the temp in them about 3-4 degrees over the room temp. I don't have heaters in them right now.

I would think the transfer of heat would be less in the HOBs that have the piece at the bottom separates the filter from the back side of the tank.

What HOB do you use? is the pump in the water or out?

edit: by pump I mean the motor

MorganWA = if you're directing the question to me....
Aquaclear HOBs and whatever little submersible pump comes with the Evolve8.

Keep in mind mechanical devices like a pump have an operating temperature and not a simple +1 to temp effect... so the same pump may help carry your 5gal from 65 to 68 and your 55gal from 65 to 66, but at higher temps it may take your 5 gal from 78 to 77 (cooler due to current and heat exchange) and your 55gal from 65.01011 to 65.01012.

Point being: Worth experimenting and monitoring what effects different equipment has! Another great source of temperature control to consider is insulation... what would happen to our tanks if we started wrapping one or three sides of the tanks with safe insulation materials?

I was asking Cory, I know the Aqueon's filter motor is submersible and I found that it increased my tanks temperature.

I'm using the Finnex canister filter with it's brackets as a hang on back filter.

http://www.finnex.net/index.php/products/filtration/filter/finnex-px-360-canister-filter.html

You know... that's not really a HOB anymore with so much filtration material But I'm not surprised that pump is generating so much heat. The AquaClear units I have all have an external pump that's well separated from the water canister in the filter. They don't seem to raise the temp too much (in fact with the waterfall effect, they may cool it. On the other hand, the finnex with the inline pump and short lines would definitely raise the temp a chunk.

As soon as I switched to the Aquaclear filter I didn't get as much heat transfer.

I'm wanting the heat transfer. Means less heater needed

ha!! I guess that is true!