Heater to hot.

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.


Aquarium Advice Addict
Jan 19, 2006
Well the lady when we got it said that a 300watt for our 50 gallon would be good because it wouldnt have to fire as much. Anyway this was fine eventhough I had to set it really low it stayed at about 78. Well then I added a maxi-jet 1200 and the temp will not go below 81 and its turned all the way down. Is there anyway to avoid buying a smaller heater? I plan on putting another 1200 in there also wich i am sure will bring up the temp even more. Im kinda irritated about this. TIA
The heater has a themostat on it that should not allow the heater to turn on if the temp is above what the themostat is set for. Now aquairum heater themostats are not the most accurate so its possible for them to be off a few degrees. A good floating thermomoter will help establish where on the heater you need to set the themostat for your desired temperature.

Most heaters also have an on indicator light. If this light is on all the time than its possible the heater's themostat is stuck in the on position. Adding the maxijet should not have increased your tank 3* unless you had way to low water movement to begin with and you had warm and cold spots in the tank. Its likly your heater's themostat is way off and you need to drop it down a few more notches even though its set at 78 and your tanks at 81. Try it at 75 and see if your tank drops a few degrees.
Another heater brand you may want to consider is Won Brothers Pro Heat 2. I say the 2 line because they actually have it so that you have 1) a digital readout on the dial. 2) the temperature adjusting dial is NOT in the aquarium, it is actually where the digital readout is located. 3) It is a titanium heater so it is virtually indistructable. and finally 4) there is a seperate probe that shows you the current temperature in your tank (connected for the digital readout). This probe not only shows you what the temperature is in the tank, but it is also the way that it tells the heater when to turn on and off.

I do agree with fishfreek about keeping a seperate thermometer in your tank, it is needed incase something does go wrong.

I keep a 50 gallon tank with a 250W heater and haven't had a problem.

Hope that helps you out
I have a digital thermomoter in it and it sits at 81.7 degrees the heater is turned all the way down. I was thinking maybe sense there is water movement past the heater it throws off the thermostat. No the indicator light isnt on all the time. The heater is in the middle of the tank and the thermomoter is on the right side. I tried moving the mater away from the heater and towards the heater and it doesnt seem to make a diffrence. The heater is this one http://www.all-glass.com/new/index.html If you look towards the bottom there is a section for the heaters.
FWIW on tanks 4feet or longer, I always suggest two heaters, and split the total wattage.

If this was my tank, I'd have two 150w heaters, one in each back corner.

Allglass heaters must be new. they could be pretty junky...hard to say as this is the first 'review' of one I've seen.

I only buy visithem and ebo jager submersibles, or Hydro ETH inline for canister filtered tanks.
Good point, Malkore, but perhaps not for the reason you intended. Two undersized heaters will not boil your fish, if one fails in the on position, the way an oversized heater will. I was just reading on another forum, where a brand new (calibrated) Jager heater cooked a tank of rare and expensive corys (around $200.00 worth). I have all, cheap, hang on back heaters that have, occasionally, stuck on, but none have been of sufficient wattage to overheat a tank. I have one Longlife 25w, that is over 40 years old, and still working. Regardless, the point is a good one, and good advice when planning a setup. The initial cost is more, but the long term peace of mond is worth it.
Top Bottom