Heater driving me crazy!

[RackinRocky]

This is weird, but true. I have three tanks. A 10 gallon, 20 gallon and 55 gallon. I use Aqueon heaters and have absolutely no problem with the 10 gallon and 55 gallon. I set the heater, tweak it until it gets the water temp I want, and that's it. I don't need to fool with it again. But on the 20 gallon, for some reason, heaters don't work right.

I posted about it either on here or another board a couple of years ago, that the heater would get down to 73-74 at night, but at the same setting, it would go up to 80 by mid-afternoon! It gets 10 degrees colder in the house at night, but even so, the other tanks are not affected by it. Some people suggested I not risk it, and replace the heater, so I did. And guess what? Same exact problem with this one! I'm especially concerned because I have Hasbrosus cories in the 20 gallon, and they shouldn't go above 78. Also I don't like it fluctuating 6-7 degrees because I know it's not good for the fish.

The heater is, by the way, a 100 wt. Anyone else have this trouble?

 

[jrc0528]

well, try a 50w or 75w, preferably a different brand altogether. Also, make sure it's in the flow from the filter so it can heat evenly.

 

[RackinRocky]

Ok, well it's nowhere near the flow from the filter, so I'll fix that immediately. I think I have a 50 wt. somewhere--I'll look. If it being in the filter flow doesn't work, I'll put in a 50 wt. Thank you!

 

[fort384]

Also consider environmental factors - is the tank near a heat vent, a window, a door, a draft, etc? It doesn't take much fluctuation in the environment around the tank to cause temp swings - while the heat capacity of water is greater than air, it still will change temperature very quickly.

 

[RackinRocky]

No, fort. That is another puzzler. It's, in fact, almost right next to my 55 gallon (only a foot away) and no nearer the window, door or draft than the 55 is. Since I've placed the heater next to the outflow of my filter a few hours ago, it's stayed exactly at 75 degrees. I prefer it at 77, but I'm afraid if I barely touch the control, it'll go up to 80 again, as it always has in the past. But night is upon me, so I guess I'd better do that, or it'll be down to 71 or 72 by morning, no doubt.