Screw the colors! I do not have another heater and this guy seems to be doing fine without one. It is the oscar that is a bit sluggish.
The summer is starting and during the day the temperatures will be in the 90's and the humidity is around 80%. Some fish like it hot but I don't. I have thirteen tanks and the heaters on them do make a difference. More than 50g of water evaporate from the tanks in my apartment between monthly water changes at this time of the year. I will unplug all of the heaters today. It's a waste.