what is a good place for a heater

[carpediem]

I had my new heater first behind plastic plants, but did not get the temp up in my 10 gal tank.
Now I moved it into the corner beside my HOB cascade filter. Still, it will not go higher than 80. (I am trying to get it to 83 for my fishless cycle with raw piece of prawn).
I have the dial at 87 right now. It will heat for a while and then shut down.
It is a Jaeger 75W.
Any ideas how I can get the temp up?

[Meredith]

Is it a fully submersable heater? If it is I keep mine pretty near the bottom at an angle.

[Devilishturtles]

My tank heater for all of my tanks are simply sitting vertical attached to the back wall.

Like already asked, is your heater submersible?

[JohnPaul]

And how big is your tank? If the heater is anything less than 5 watts per gallon of water, don't expect it to be able to do the job.

Sadly, often pre-packets aquarium starter kits contain heaters that are too small. I just got one of those kits for a 29 [acronym:81f618ec86="Gallon"]gal[/acronym:81f618ec86] tank; stupid heater that came with it was only a 100 W heater. Which is fine if I am just raising the temp a few degrees above room temperature. But when my heat (as in, my building's heat) went out for a day and my room temp dropped to around 68, my heater was unable to maintain my tank even at 76.

If your tank is larger than 15 [acronym:81f618ec86="Gallon"]gal[/acronym:81f618ec86], I would suggest a new heater.

[Fishyfanatic]

We have the 150 [acronym:db8a2faf3f="Gallon"]gal[/acronym:db8a2faf3f] heaters verticle at every 1/4 mark in the tank (3 heaters total). On all the others, it is horizontal a couple inches from the bottom in the center.

[carpediem]

It is a Jaeger (now made by Eheim) 75W Model TS.
It has a water-level indicator on it, but the lady at the [acronym:ce7a9bb563="Local Fish Store"]lfs[/acronym:ce7a9bb563] said, it is fully submersible. Has anybody experience with it? Is it now fully submersible, or not?

According to the package, the 75W should be enough for 15 to 20 [acronym:ce7a9bb563="Gallon"]gal[/acronym:ce7a9bb563], so therefore should be plenty for my tank. It has one of those dials on the top to adjust the temp. At a setting of 87, my water (since last night) is still just below 80.
Am I doing something wrong?

[JohnPaul]

Ok, first rule of thumb, *never* trust what it says on the package. :P In my (short) time having an aquarium, I have learned that lesson on several occasions already, once to a very significant degree (trusting a package when it said the antibiotic was "safe" for my biofilter..and a few days later having my biofilter entirely destroyed...0% ability to process ammonia. So I'm now ~ 2 weeks in to re-cycling my tank. grrrrr )

If you have a 15 [acronym:1a408813d7="Gallon"]gal[/acronym:1a408813d7] tank, a 75 W heater *should* be fine. If you have a 20 [acronym:1a408813d7="Gallon"]gal[/acronym:1a408813d7] tank, and you are trying to get the temp up beyond 80*F, I think the heater package can make claims until the cows come home--I simply don't think it has enough "juice" to raise the water to the temp you want.

Now, that being said, let's examine what you have. If the thermostat on the heater is set for 87*F and it is not getting your water above 80*F, and yet the heater is turning off, then I would say you have a faulty heater. A heater should not turn off until it is sensing that the water around it is the temperature the thermostat is set at. So it sounds to me like your heater "thinks" it is successfully getting the water to 87*F. I suspect the internal thermometer within the heater is miscalibrated or broken in some way.

I wish I could help with the fully submersible issue, but I am confused and perplexed by that as well.

[QTOFFER]

What is the temperature in the room where the tank is located? When the manufacturers rate their heaters, they assume that you'll be raising the water temp just 5 - 10 degrees above ambient room temp.

The other possibility, already brought up, is that the heater's thermostat is out of calibration. If it's a new heater, you might bring it back and exchange it for another.

[TomK2]

I would think a 75w heater in a 10 [acronym:30c5d6f346="Gallon"]gal[/acronym:30c5d6f346] tank should be able to raise the temp 14 degrees or more above room temp. Since it is shutting off, I bet it is defective.

If it has a "maximum water depth line," it is probably non submersible, since they don't want it in any further. If it has a "minimum depth water line" it probably is submersible, since they want it in at least that far. Make sense?

[Fishyfanatic]

Could the thermometer be reading the temp wrong? What kind of thermometer do you have? Stick on? Digital?