I have a sump filter system in my 120 gal tank. So I am having problems keeping my water temp down - previously posted that I am putting frozen 2 liter bottles in one of the sump compartments and that helps to drop the temp. However, the temp does not stay that way. Even if the temp in the house is only 74-75 degrees the tank temp will get up to 82 degrees (no light on either). The tank is not in direct sun either. Granted I live in FL but the inside of the house is cool.

Is it possible that the pump, which is hot to the touch, is heating the water?

If the pump is getting very hot then yes,that will act as a heater. However, if it is getting too hot to touch than I would be a little concerned about that. I think I would be inclined to get another pump.

the main reason i used a pump from a central heating system, that it will give off almost no heat to the water.
But hot to the touch seems a bit much.
The temps in my tank fluctuate with the surroundings, so if room temp is dropping, the tankwater shouldt drop too.

Im in the UK im having the same problem to be honest keeping my tanks temp down.

I leave the lids open in the day time and keep the lights off ....my tanks are also not in direct sunlight yet the temp still sits at 28-29. although i have just done a water change and this seems to bring the temp down a little. I have also unplugged my heaters as i think although they have thermostats and dont come on when its hot..some heaters have a funny 5 mins if there is a cooler spot in your tank ...some of you guys have totaly massive tanks and i guess its harder to regulate the entire tanks tempreture when your talking 200 gallons etc etc

STAFFIE wrote:


I have 150g(uk) and have no problem at all keeping the temp stable. i keep my temp at 28c all yr round so wouldn't worry staffie.

as for brooksie as ofl said yes the pump can heat the water, if its over hot I would be concerned but warm is normal. do you have heaters??? I know a few of you lucky FL residents don't use them. this would be my 1st place to look. you can buy tank coolers also and may be worth looking into.

so 28c is ok as a base temp? I thought it was best to keep it down at more like 24-26 by what I have read on some threads...that has put my mind at rest a little marcus cheers. I was just a little worried as my living room is heated by the sun all day long pretty much and its almost unbearable... I have to run two big tower fans just so the family can use the living room comfortably.

I do have a heater - not plugged in but left hanging in the tank because the Pleco likes to hide by it. The pump is not too hot to touch but runs warm (better explanation). Again, the tank is not in any sun light. When I do a water change the new water going in is 82 degrees so that is no help. I actually felt the water coming from the pump... not overly hot, same temp as the whole tank.

Where can you find tank coolers?


Staffie... thank you! I was starting to feel alone in this water temp issue! I can not leave my tank lid open, already had a death due to a jumping Oscar (with glass lids down).

I am not suggesting you buy from this shop as I have never used them nor have i ever used a cooler. but this will give you some idea of what to look for, makes and models,what's available. you may need to put a bit of research in, as some of these are not cheap, and i don't know what its like to run them? hope this was of some help. sorry I don't know more about them, some of the other may be how to help?

www.onlineaquariumstore.com/acatalog/Aquarium_Cooling.html

If your tank is warmer than your room then that implies something is heating the water. If it not heaters then is does sound like the pump is warming the water so i would look at getting a new pump

Thanks... looking into both. First would be the pump since it came with the tank and the age is unknow.

Thanks everyone !!!