I'm working on setting up a 44g hex corner tank, and I was thinging about running a 250w MH retrofit setup. I know MH get hot... but how hot? Can a 250w bulb be put into a retrofit kit for a standard strip light without worrying about heat?
you can't avoid heat production when you add a light source, but you can evacuate the heated air by opening the canopy or by installing a fan(s) to create an air exchange..cooler air for heated air. on my tank the 4" fan is worth 2-3 degrees of temperature.
What makes a big differents is the surface area of yor tank and the distance you place you light from the top of your tank and the size of your sump and yes I would put a fan on the hood.
Another option would be hanging a halide pendant from the ceiling. Just a thought.
matt rogers
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