Mj1200 causing my tank to heat up.

Fishyj · Oct 16, 2016

Hi , I have a mj1200 pump that I am using on my 13.5 aio. The tank was setup today and I have noticed that the temperature has been going up .2 degrees every so often. The heater is on a temp controller and that's been unplugged. The light is not hot at all. The only pump running is the mj1200. I never noticed a problem with it on my other tank. Will all pumps heat the water to some degree? The tank temp as of now is 81.6. Any suggestions?

Sabellafella · Oct 16, 2016

Fishyj said:
Hi , I have a mj1200 pump that I am using on my 13.5 aio. The tank was setup today and I have noticed that the temperature has been going up .2 degrees every so often. The heater is on a temp controller and that's been unplugged. The light is not hot at all. The only pump running is the mj1200. I never noticed a problem with it on my other tank. Will all pumps heat the water to some degree? The tank temp as of now is 81.6. Any suggestions?

Any internal type of pump would yes indeed heat the water to some degree. Since your tank is only 13.5 gallons, maybe the "heat issue" is more likely to happen, compared to lets say a larger tank. Give it a few more days and report back with the exact temp swing. Try not to have more then a 2° swing daily, and the actual temp is up to you. Id try to keep it under 81.

mcarroll · Oct 16, 2016

A 30-watt heater will heat the water the same amount as a 30-watt pump or 30-watts of light, more or less.

A heater just doesn't do anything with the watts other than heat the water. Even the light from your fixture mostly ends up as heat in the tank.

We're thankful about LED's in large-part because they don't start as much of that light-power off as infra-red. IR light doesn't do anything except heat the tank. Even the rest of the wavelengths end up as IR-then-heat as energy is lost.

Law of conservation of mass and all that.

MaxiJets are not very efficient water-movers.....just good utility pumps.

Switch to something like a Turbelle® nanostream® 6020 ($43) – it moves twice the rated amount of water of a maxijet 1200, but only uses 4 watts to do it.

A Turbelle® nanostream® 6015 ($40) would also be a nice option:

Fishyj · Oct 16, 2016

Thanks, I will look into them.

Fishyj · Oct 16, 2016

I looked at them but they are not return pumps. I put the original one back in and my temps are now 77.6 to 79.2. The problem is that I need more flow in the tank. I was trying to do this with 1 pump. Any other suggestions on a return pump that won't overheat my tank.

Sabellafella · Oct 16, 2016

Fishyj said:
I looked at them but they are not return pumps. I put the original one back in and my temps are now 77.6 to 79.2. The problem is that I need more flow in the tank. I was trying to do this with 1 pump. Any other suggestions on a return pump that won't overheat my tank.

Hmm, unfortunantly i dont think there is an internal pump that doesnt create heat. Of your looking for more flow, get like a jebao or an ehiem or sicce . They work great! But again, they still produce some heat. Maybe try a fan on your tank, or open the lid will keep the temps down

tomtom2245 · Oct 16, 2016

Look at the Rio pumps. I have one running as a return on my 3.5gal AIO with no heat problems at all.

mcarroll · Oct 16, 2016

I'm not sure that's what you were after, but I was saying you could add one of these for more flow rather than doing it with a large return pump.

Are you sure the tank would have overheated with the MaxiJet? Most people wouldn't elect to keep their tanks at this temp, but anything up to 84ºF and maybe even a bit higher could work fine.

Thing is, evaporation usually kicks in pretty hard once temps go up and that keeps things from getting much hotter....I think my tank with halides that stayed around 83ºF and was great. I did have a fan as a backup, but it'd never kick on.

2¢