Need a new thermostat, but dont know what spec i need

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Aquarium Advice Freak
Dec 13, 2005
I think i need to purchase a new thermostat for my 30G jewel aquarium. This aquarium was given to me by a lady at work whos son didnt want it anymore. I dont know how old the thermostat is, but the other morning i noticed the temp was lower than it normally is, by about 3 or 4C. I adjusted it, and it seems fine, but for peace of mind, i want a new one.
Another problem with my current one is, it has no temp markings, so you just have to guess how far to turn the adjustment, then see how accurate you were later by reading the thermometer!

My tank is the Jewel rekord 120 (29G)

Any suggestions? Thanks in advance
I would say get a new heater. Even on new ones, don't go by the temp on the knob, most are inaccurate. Use a thermometer or digital thermometer to monitor the tank temp, then adjust the heater according to the thermometer reading. And don't use the thermometer that sticks to the glass, it's highly inaccurate.
the older heaters did not have numbers and they worked flawlessley IME.. and yes you had to adjust them by your thermometer.. its wise to do the same with a new one..

I think I understood that correctly..

when the old ones went bad they did not louse temperature usually they cooked the tank (they got stuck on).. soo.. its either your thermometer or the heater is undersized IMHO.

I should note the older heaters that didnt have numbers that I used were Jebo's so that may have bearing on why they worked flawlessly.. :p
Ok, thanks. So what wattage would i need? I have no idea what the current one is.
Do you mean the flat thermometers that stick to the glass? The ones that colour up on a certain figure to indicate water temp?
I have always gone by the 5 watts per gallon rule..
For cheap thromometers nothing beats a glass one, either one that has a suction cup or stainless steel hanger that goes in the tank.. (so long as you dont have monster fish to break them.. LOL)
and it looks like you would be fine with a glass one.. (I can get them for 88 cents localy so I have a handfull of them)

btw.. you dont happen to have a way of knowing how many watts your heater is do you? is it printed on the heater somewere?
elliott_001 said:
Do you mean the flat thermometers that stick to the glass? The ones that colour up on a certain figure to indicate water temp?

Those ones are very inaccurate. Glass thermometers are cheap, and works great in the tank. Also the digitals with the probe that goes in the tanks are great also, but costs a little more. All depends on how much you are willing to spend.
No, im pretty sure that it's not printed on the side, but i will double check.

I have one of the glass thermometers with a suction pad. I was just checking.
Digitals are about $6 around here and are great for accuracy. They can be read with a simple glance. I bought one about a year ago and ever since then we've replaced all the glass ones with the digis.

A 150 Watt heater would be the size for your tank. The Visi-Therm Stealth is an awesome heater that won't break like glass. It has an auto-shut off so you don't have to unplug it before taking it out of the water. I pretty much go by the number on the top of the heater for the temp in the tank. Maybe I'm just lucky with the room temp because it seems to almost always be exactly what it is set at.
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