Largest powerhead without a power supply and controller

[Lukas75]

A friend gave me a mag 18 a couple weeks ago and I glued a ceramic magnet on the back to hold it to the side of the barrel.
I tested it out yesterday in my 70 gallon water change barrel.
I let it mix out overnight and was going to do a water change first thing this morning.
Fortunately I tested the water temp before removing any water from the display tank.
The water temp was 86.8. It was all from the pump. I forgot to add a heater to the barrel.

I have the same issues with my mag drives. More than once I've had to actually put ice in zip lock bags to get the temperature down to do a water change. I still use it, but once the water clears I pull it and use an old Koralia 300 just to keep it moving until I'm ready to use it. When I get a little extra money, to put into mixing and not the tank, I'll probably get a Sicce too.