I had a tank when I was.. oh.. about 10?
So about 6 years ago, it was a tropical tank, and there was a heater in it.
Can I still 'trust' such an old heater?
I dont know how these things work eithier o_O

So uhh
Help?
Advice? XD

Well, once again, the answer is yes and no.

Heaters are one of the parts of the fish tank that tend to have fairly short lives. The cheaper the heater, the shorter the life. Most of the really cheap ones last about 1 year if you are lucky.

So.....if the heater is one of the kind that has a line on it that says "water level", I would ditch it. Heaters now-a-days are much more commonly found to be "fully submersible". Getting one that can be placed all the way under the water will go a long way to prevent one of the most common reasons for heater failure - coming out of the water during a water change and cracking from overheating. You MUST unplug and wait for a heater to cool before changing the water. If you have a fully submersible one, you can stick it, horizontally, across the bottom of the side glass of the tank. I like to put a bubble bar right underneath the heater so that the bubbles come up and across the heater. This distributes the heat quite well.

A heater placed low like this usually will not come out the water during water changes and will not crack.

There are numbers of types of heaters. For goldies, you really do not need one on a regular basis for your average adult, healthy goldfish. THey come in handy for sick fish, fry, or during a VERY cold spell in your house. But in general, you probably will not need one all the time.

I've used heaters that are about 15+ years old and they worked.. but not very well.. and I think one tried to electrocute me.