Heater making me boil

[Arizonagrace]

I bought a new heater for my aquarium so I can adjust the temperature in the tank. The one I did have is one that has no adjustable knob. I brought it home, opened it and it was broken. I took it back and exchanged it, checked it out thoroughly, and installed it. I let it sit in the tank for about an hour before turning it on and removing the old one. I installed it according to directions and was very careful. It seemed to work okay for the first day, and I raised the temp by 2 degrees. This morning, I woke up to find the tank back at the original temperature. I tried to adjust the heater to find it wasn't working. I looked at it and realized it was full of water. I unplugged it and very carefully removed it and installed the old one. The new one has water all through the inside, and there is brown stuff in there. When I wiped it off with a towel, I got a lot of the brown stuff on the towel.
I am really upset that 2 of these heaters were bad. I guess I am more concerned thinking of what could have happened if I didn't check my tank 8 times a day.

Does anyone think this will hurt the fish I have? I don't believe anything from inside the heater got into the water, but I am not sure.

This was an Elite Radiant 100w, 8 inch heater. Now, I have to drive 12 miles to replace it one again. I will get a different kind this time but I am not sure what brand to buy.

 

[Angler]

What a pain. I think your fish will be fine. Get a Stealth.

 

[Dr Joe]

Your not fully submerging this heater are you?

Isn't this one a hang-on heater.

 

[Wolf3101]

Yes those are NOT submersable heaters. In fact they are not even good HOB heaters as your finding out.

 

[Arizonagrace]

No, I did not submerge that heater. It is an hob.

 

[Alistriwen]

I buy cheap economy heaters from jehmco.com and they work fantastic.

 

[cichlid savage]

I swear by stealth heaters. Never had any problems with them.