Submersible Heater Question

WaterBaby

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Sep 23, 2002
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I have a submersible heater in my tank (6 gallon eclipse).

When I do water changes, I unplug the heater because the water level drops to the point where the top of the heater is out of the water.

Question is: Do I really have to unplug the heater? How much of the heater (if any) can be exposed? There was nothing in the instructions to tell me anything.
 
I unplug all my heaters when doing water changes. Better safe than sorry. I don't think the element should be out of the water, if the air temp is cooler and the heater turns on, the glass could crack, I think. That happened to me once many years ago when I tried to keep a very shallow bit of water warm for a turtle.

However, usually there is a "water level" mark on heaters. If your level doesn't go below that marking (if it has one), it should be fine.
 
Even if you don't expose the heating element during water changes, you may expose enough of the heater to cooler air that it will turn on the heater. In such a small tank, having the thermostat calling for heat could call cause the temp to spike more than is desirable. Definitely safer to unplug.

HTH,
Jim
 
Well, I don't want to be the "devil" but I leave mine on always, even in my 10 gallon. During water changes I'd say about 1/4 of the heater is exposed and I haven't had any problems and if you have a quality heater, you shouldn't either.
 
Some heaters are supposed to be able to sense when they're exposed to air and shut themselves off. Many heaters don't have this feature, though, and many people have shattered heaters in their tanks doing what you advocate.

Jim
 
When i change my tank i just turn down the thermostat. That way the heater wont come on when i am doing my water change. You just have to remember to turn you heater back up to the desited temperature. Its a whole lot easier than pulling plugs!
 
I have most of my "tank plugs" going into one surge protector, so I just turn off the surge protector - it gets the light, the filter, and the heater all at the same time. I don't turn off my airstone because it's low enough not to matter.

I never knew that heaters really would shatter, but I've always been paranoid enough not test the theory.
 
I agree with turning the heater off during the water change.
And I also have the heater(s) and filters on a 'power strip' so you can push a switch to turn them all off. It's fine to leave a air stone running during the water change.

Don't forget and keep your 'tank' water and 'new' water very close in temperature so you don't stress the fish..
 
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Despite the "water level" label a truly submersible heater, such as an Ebo-Jaeger, is totally submersible. This question comes up periodically on a number of fish forums. I contacted Marineland ( makers of Visi-therm ) who confirmed that you can put them on the bottom if you wish. I know this seems contradictory to the "water level" line, but it does seem to be the case. An experienced aquarist suggested that by law the label is supposed to be there, but they are submersible. I do agree it is safer to unplug during a change ....but if it is low enough ( or placed horizontally), it won't be exposed anyway.
 
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