2 heaters?

i have a 72 gal aand i have a ehiem idk what watt(i think in sig.) would i need 2 heater?. just have 2 bta mushrooms and ricordeas. is it not needed?

 

i have one 250 watt heater (sorry i didnt feel like looking before)

 

I think your alright on one heater being that it is a 250 watt in a 72 gallon and I think I only have a one 250 or 300w in my 90gallon but sometimes people like to run 2 smaller watt heaters.....others will run one heater of a higher wattage but will have another on backup waiting in case the other goes out soon

 

It is better to run two just in case it gets too low. Run the second one lower then your normal temperature. It is best to run two smaller watt heaters because you wont have one that stays on and spikes your temp too much, the chances of both malfunctioning at the same time is remote. I run 2 200w heaters on my 65.

 

Many people have many reasons for doing things many different ways in their tanks. Some of the the reasons for running 2 heaters are:

Deliberately running two 'smaller' heaters because when (notice I did not say 'if') a heater fails, they often fail in the ON position. Running lower wattage heaters will minimize how quickly a failed heater can cook your tank.

Second reason is that having a second heater provides some insurance against your tank getting too cold if the first heater fails in the OFF position.