Used heaters... wattage?

[equus_peduus]

I have four used aquarium heaters, and not sure what wattage they are (dunno if they all work either ) All are hang-on-tank type, not submersible. They all either came with something else I bought, or were free.

One has no identification as to brand... it says "Aquarium Heater" on a blue/teal label with a black knob. The glass is about 7.5" long, 3/4" diameter.

One says "Aquaculture Aquarium Heater" on a blue/teal label and has a red knob. 11.5" x 0.5"

The other two are Penn-Plax therma flow "PC"
One is 7.5" x 1"
The other is 11.5" x 1"
The internet tells me that there is a 12" 150W heater, but there are four choices as to 8" long ones.

And what's the best way to tell if they still work right? Hang 'em on a bucket with some water and a thermometer? Or fill up my (currently empty 55ish) tank and see if the water temp stays semi-stable?

(edited: found one more heater after digging a little more)

 

[Rbishop]

A bucket will tell you if they work.

 

[Weezer]

Yep.........

 

[fishorama]

I never had good luck with hang on heaters, they seem more prone to overheat or not work than submersibles. They are hard to hang on some tanks & easy to bump out of position. Be careful.

 

[wataugachicken]

i got two hang-on heaters with tanks bought off ebay. I really don't trust them as much and therefore have not used or tested them because personally i am not able/willing to keep my water level up that high every day. sometimes the "water level" on the heaters is somewhere far above the trim of the tank.

 

[rsw686]

Heaters are cheap enough that you should just buy a new one. After they are used for awhile the bi-metal strip inside can stick in the on position and it will cook your tank.

It's also better to get a couple smaller heaters than one large heater. If you need 400 watts, get two 200 watt heaters. If one breaks then you'll still have some heat. If one sticks on it will take longer to affect the overall tank temperature.

Regardless of which heater you use, you should invest in a controller like the Ranco. This will protect your tank in the event the heater sticks on.