I have a heater contained in the filter box of my Juwel tank and I want to know if it is OK to have my 2nd heater in the tank,uncovered, as a backup in the event of the other one breaking down. I know the LFS's have them loose but I just want to be sure. Don't want to come back from hols to find fishys all burned.

Thanks
Processor.

I've never had a problem doing this (having a heater in the tank) but I'd also check the mfg booklet on the heater and ensure you comply with the right setup.

Are you running both heaters at the same time ? If you are I'd make sure they are set to the correct temp individually before having both turned on so if one does fail it is set up correctly.

My question - Would both compete to heat the water when both running ? Would guess so and expect that one would always win unless that were identical in every way, including setup.

Monty

I run 2 heaters in some of my tanks with no problems.
The only time i use covers on them is when i have pleco's in the tank.
The pleco's can get burnt resting on them.