wattage per gallon - heaters

f8fan

MFT Staff
Nov 19, 2004
1,765
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Bangor, Maine
#1
what is the rule of thumb for heating a tank for wattage? My little 5 gallon tank's heater seems to have got kaput and I need to get a new one. Would a 50 watt one be ok? Big Al's has a nice little one for like 6 bucks....
 

f8fan

MFT Staff
Nov 19, 2004
1,765
8
38
Bangor, Maine
#2
well, I ordered it anyway. It was a great deal only 4.99...I llove Big Als online! Highly recommend it for anyone looking for a great deal and don't mind the couple/few days for shipment. I ordered a powerhead, a heater, a hydrometer with attached thermometer and a lovely silk plant for under 30 bucks!!!!!:D
 

f8fan

MFT Staff
Nov 19, 2004
1,765
8
38
Bangor, Maine
#7
ok azndeath, at 6 bucks it is not a big loss. I will look for a 25 watt heater tomorrow. The tank is located in my office at work and the heat is set at 70, so although this isn't the optimum temperature for a betta (the only inhabitant in the tank) I feel pretty safe that it is doing better in a nice 5 gallon filtered tank than an ornamental vase with three teaspoons of water and a heck of a lot of plant roots to "eat". I will see that I find a 25 watt tomorrow and keep the 50 watt as a "spare" backup for an occation that might arrise. Thanks for your responce....
 

TurbineSurgeon

Superstar Fish
Feb 27, 2004
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Dallas, TX
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#8
5 watts per gallon should usually suffice if you only need to keep the water temperature about 10 degrees above room temperature. If the room gets colder, a bigger heater is needed.

The potential problem with having a bigger heater than is needed is that if the heater malfunctions and sticks in the "on" position, you could have fish soup on your hands. A smaller heater would give you more time to react.

Check out the table about half way down this page for more detail.
 

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