How high to place my MH

[fishes2889]

Hw high should i place my 250w MH w/ an 18in reflector over a 40g breeder? Dimensions are 36x18x18....

Thanks :)

[Entropy]

Mine is about 12 inches up in my current config. I made the canopy pretty big so there would be more air space for cooling. I have had 175w SE's as close as 3.5 inches without an issue. I would try different heights with the reflector to see what looks best.

36x18x18 is 50g by the way. :)

[fishes2889]

ahh yeah i meant 16" height wise :).....

i guess i have to play around with the height....

[fishes2889]

Any other setups guys/gals? :)

[Leopard Man]

I have 400w over a 40x18x18 and it's 14" off the water. Works great.