Originally Posted by jtrzerocool
yes MH's produce ALOT of heat. i have 2x150x MH's on a 50g without a cover with no problem but with 150w of metal hailde on a 29g covered tank i find it hard to belive that you can get away without a chiller.
Yea it may be iffy without a chiller, but I say go for the MHs, but make sure if you need a chiller, you can afford to get one because they arent cheap.
Another thing that may help with the heat is hanging the lights higher from the water, but this also reduces the effectiveness of the lights.