Strange Acting Tank Heater

Dec 5, 2011
268
0
0
Walla Walla, Washington
#1
I recently bought a heater for my tank, but when i first tried it, it was heating the water up way too hot (80 - 90 degrees). Now, when i turn it on, it only raises the temp. about 1-2 degrees (71 - 73 degrees ). When i took it out of the water, it started to get warm in my hands, so i put it back. It didn't do anything. What do you think is the problem?

BTW, the heater is the flat kind that you bury under the gravel.
It is for 5 -15 gallon tanks.
 

Thyra

Superstar Fish
Jun 2, 2010
1,891
0
0
Yelm, WA
#2
I do not know anything about that type of heater, but if you bought it and right away it did that, why didn't you return it? I do not think heaters are a "fixable" item - they either work or don't work. Personally, I would be skeptical of any undergravel heater that would adequately heat a 10g tank. I have one submersible non-adjustable heater for a 2.5g tank and it does a marginal job although its rated for 2 - 10g. I would not buy another preset, unadjustable heater.
 

Dec 5, 2011
268
0
0
Walla Walla, Washington
#3
Yes, this heater is unadjustable, but i can't return it because i don't have the packaging or receipt. I guess I will buy a new adjustable heater, but I would still like to know the source of the heater's problem. I tried plugging it into various outlets, using the suction cup ( that came with it ) to just put it on the side of the tank so the fish could go there when they got cold, and using several different thermometers to tell the temp, but the crazy thing still has problems.
 

Lotus

Ultimate Fish
Moderator
Aug 26, 2003
15,115
13
38
Southern California
home.earthlink.net
#4
Just so you know, a lot of heaters will stop working completely if you take them out of the water while they're plugged in.

I'd suggest an adjustable heater. They're more expensive, but that's better than boiling/freezing your fish.
 

Kiara1125

Superstar Fish
Jan 12, 2011
1,142
0
0
Florida
#7
SlateSpider said:
Part of the problem may be that i left the heater in the water, unplugged, for a week or two.
That wouldn't have anything to do with the problem. In the summer time, I turn off my heaters but keep them in the water and the water goes up to 86 degrees. My fish don't mind, since it's gradual, but if it's overnight then you have a right to worry. I have Tetra Submersible Heaters. What type of heater is yours? Are you sure that it is submersible and that it's for aquariums? I've never heard of an undergravel heater. If you want to, you can get a 50 watt Tetra Submersible Heater. It's non-adjustable, but it's fully submersible and it keeps my tanks around 74-76 degrees which is perfect for the type of fish you have. The 50 watt heater is for 5-15 gallon tanks and they cost $15 at Walmart.

Good luck to you and your fish, but for now, I would just not use the heater and put a small lamp over your tank and monitor the temperature carefully. Of course, this is only until you get a heater.
 

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Dec 5, 2011
268
0
0
Walla Walla, Washington
#9
My heater is a "Slim Heater". It says that it is for 'Micro tanks and Mini aquariums'. That is all I saved from the package.
I don't have the rest of the packaging, so i don't know the brand or anything. I got it from Petco, down the street. You're supposed to bury it under the gravel, but i just suction cupped it to the side of the tank for now.
 

skjl47

Large Fish
Nov 13, 2010
712
0
0
Northeastern Tennessee.
#11
Hello; The heaters that hang on the side of a tank with the glass tube in the water and the top out of the water are easty to adjust. I have also been able to fix several of them over time. The problems have often been with the small contact points on the bi-metal strips. Often a simple smoothing of the points with a metal file will restore the function of the thermostat and get the heater back into service. I find that some small adjustments are often needed with the change of seasons which is a simple turn of the adjustment knob on the top.
I have a submersible heater that came with a used tank but have not used it as yet. The concept of an electrical device that carries the current of a heater being submerged make me wary. If something goes wrong, it has the potential to go very wrong. The type on the side have only the glass tube in the water and with the modern tanks with plastic rims should be very safe. To each his own, but the safety concern currently overides what ever advantages there may be to a submersible heater. I plan to change my wall outlets used for the tanks to the GFI type and may feel more comfortable after that.
By the way, what are the advantages of a submersible heater?
 

KcMopar

Superstar Fish
#14
I don't know if i'm just reading too fast or what, but where did you get that the heater was Penn Texx??
I was referring to the heater being unplugged ,as in it was cheap. I was saying that penn texx had OK quality heaters. Not the best, not the worst but, OK.
EDIT: My mistake they are penn plax brand, sorry for the mistake. Called Cascade on the package.
 

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Thyra

Superstar Fish
Jun 2, 2010
1,891
0
0
Yelm, WA
#15
I do not believe that the 50 watt heater that is not adjustable from Walmart (Tetra) will work good enough in a 10g tank. Mine, as I said before, is barely adequate for a 2.5g. For another couple of dollars you can get an adjustable one. Most of them as I understand have a fail safe system so if something breaks, the heater shuts off. I guess I worry more about the non-submersible ones falling into the water.
 

Kiara1125

Superstar Fish
Jan 12, 2011
1,142
0
0
Florida
#16
Well thyra, my heaters work fine. I can't find cheap adjustable heaters. I like them because I don't like having to constantly check the temperature in my tanks. I have an Elite adjustable heater and I don't understand how to use it. It has a knob, but it always goes overboard and heats my tank up into the 80s. Plus I think that it stays on and never turns off once it hats up my tank. I don't want to constantly keep turning the heater on and off.
 

skjl47

Large Fish
Nov 13, 2010
712
0
0
Northeastern Tennessee.
#17
Well thyra, my heaters work fine. I can't find cheap adjustable heaters. I like them because I don't like having to constantly check the temperature in my tanks. I have an Elite adjustable heater and I don't understand how to use it. It has a knob, but it always goes overboard and heats my tank up into the 80s. Plus I think that it stays on and never turns off once it hats up my tank. I don't want to constantly keep turning the heater on and off.
hello; The method I use to set the thermostat follows; I turn the adjustment knob out to a low setting so that it does not come on when plugged in. I place it in the water unplugged for about a half hour or more. Plug it in and slowly turn the knob untill the indicator light just comes on without flickering. Go away for around ten minutes or so and then check the temperature. If still too low turn the adjustment knob ever so slightly untill the light just comes on and stays on again. Go away again for a while and check it later. Keep this sequence up untill the desired temp is reached. If too high go the other way in steps. The adjustment on most heaters is somewhat sensitive in my experience and the knob has to be turned only slightly to get to the final settings.
 

Feb 27, 2009
4,395
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36
#18
Go away for around ten minutes or so and then check the temperature.
skjl47 - I have used the same methods you do to set thermometers in aquariums for many years. The only thing I do differently is that I wait an hour between adjustments (good weekend day project while doing household chores for me).
 

Feb 27, 2009
4,395
0
36
#19
i can't return it because i don't have the packaging or receipt.
I don't have the rest of the packaging, so i don't know the brand or anything. I got it from Petco, down the street.
The Petco in my area will take a defective item back without a receipt for store credit. You might want to discuss it with your Petco. You may be able to replace it with the same item or perhaps you can use the credit they may give you to buy an upgraded heater (adjustable).
 

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