I have one of those Tetra pre-set submersible heaters for 2-15 gallons in my 3 gallon tank, it keep my tank at about 77* so I was wondering if I got the same one for my 1.5 gallon if it'd be okay?

I figure in a 1.5 gallon it would keep the water at about 78 or 79*.

I know there are a lot of bad reviews for this heater because it doesn't heat anything over 3 gallons very well but it has worked fine for my 3 gallon since I bought it a few months ago, and the only other heater you can buy around here is an adjustable one that is $28, where as this heater is only $11.

I just don't want to buy it and then have it fry my fish.

This one has really good reviews..and it is only4 dollars more than the preset.
http://www.amazon.com/Hagen-Mini-Submersible-Heater-Watt/dp/B00106X8QG

I plan on replacing my tetra with that hagen eventually..

If you decide to go with the tetra though I believe it should be ok...just keep an eye on the temperature...It is preset to 78 and I have never seen one go past 78...but you never know...

 

Wow!! That's actually the EXACT same heater that's $28 dollars here!

 

Never trust any heater. Any heater could be the heater from hell.

Spot check your tank water once a week (or sooner, if your fish look distressed). I use an ordinary, accurate meat thermometer (only for fish use) to do my spot checks.

I have the same tetra heater as you in my five gallon... it is working fine now, although it couldn't keep the tank heated adequetely in the winter. I replaced it with another heater.

The new heater got moved to the 20H. The 5 gallon got the tetra heater back when I moved the set-up to a warmer room. The tetra is now adequate for the five gallon.

Before next winter, I plan to have a back-up available in case the tetra isn't enough. Then the tetra will be an emergency heater for QT and such.