External pumps really add that much heat?
 

OK, I'm still having heat issues on my 150g tank. I'm wondering if it's pumps? The 45g seems to stay at 78 and need heaters at night, where the 150 is still up to 80+ during day, and maybe 78-79 at night. heres the lowdown on them


The 45g has
1 mag 350 run external
1 quiet one run internal
1 Ehiem 1040 run internal
1 Koralia 2 powerhead
4 24W T5 lights


the 150g has
Dolphin AmpMaster 3000 external
Little Giant 4 Mqdx external
maxi-jet 400 and 900 on skimmer, internal
2 150W pendants
1 250W pendants

Both tanks are open tops and closed up sump cabinets. Except the 150, I have to keep the sump door open or else it won't cool past 79. I know the act of pumping produces some heat, but there is little head on both pumps. Could it just be the sump cabinet ambient heat? I do have a 4" computer fan sucking air into the sump where the pumps are, and another 4" blowing down across the sump water. Also, there is a 6" clip on desk fan that comes on/off with the lights on top of the tank.

I'm just loosing over 1g a day on the 150 and it's causing alot of moisture in the house. If I cover tank to reduce evap, then the temp climbs... can't afford a chiller, nor do I have space for one.

The major difference is actually a result from the volume, the 45 gallon cools quicker and easier because the total volume of water is lower. The 150 gallon will get most of the heat from the lighting but it takes more effort to extract that heat because of the higher volume. Try maintaining your 150 temp at 80F instead of 78F. This will increase the temperature gradient of the tank and the room and reduce the temperature gradient of the tank and the lighting, this will result in a lower overall temperature swing.

The pumps are adding little heat, experiment if you like by keeping the lights off one day and monitoring the temperature. Also try turning off one of the pumps in a separate experiment if possible.

What is the ambient temperature in your house where the tanks are?

can't turn off the pumps, they are only means of flow. One for closed loop, other for sump.


Russell, House temp is 71 day, 65 night. It's not the temp swings i'm really worried about, it's the evaporation. I know theres gona be evap, but 1-1.5g a day? That's alot of water into my air, and walls, carpets etc.

You could certainly turn off the closed loop pump for a day to verify it doesn't add significant heat. Same as turning of lights for one day but to verify they do add significant heat.

Only way to stop evaporation is by using lids. To prevent moisture build up in the house you can either vent out the humid air or use a dehumidifier. If it's that much of a concern and you can't afford the fixes you need to rethink your tanks. You could downsize or change the larger one into a fish only with lower lighting and lids.

Neither of the External Pumps that you are using are known for increasing the heat within the tank. They may add heat to the room however it shouldn't be enough to increase the water temp.

The increase in the water temp is probably a result of the Lighting.

It is very difficult to reduce the amount of evaporation and still have a healthy tank.

It will probably be much easier to control the evaporation with water top off and ventilation.

Tom R

run a chiller, this is the best way to reduce the amount of evap. on my 90 I went from 5gal a day evap to 2.5 by running a chiller and getting rid of the fans, also reaiming your powerheads to reduce the amount of surface agatation will help.

Steve

I agree, it most likely the lights adding the heat not the pumps. My 135 runs much warmer with the MH lights on it than my 50 with just CF light. The 50 needs heaters on to keep the temp up in spite of having all submersed pumps and powerheads. The 135 needs fans to keep the temp down once the lights come on.

what are you worried about? its gonna be minus 30 in a month. hold out, youll be buying more heaters soon!

LOL, Ian, true.

Ya I guess I just don't realize how much heat the MH produce. Hopefully this winter I'll sell all my 150's and 175's, get just 1 more 250 and a Lumenarc, and a couple T5's. ohh build a canopy and vent outside too LOL