minimum height for MH?

[bprewit]

I had to do some work to my hood today and ended up moving my VHO bulbs higher in the canopy. They are about 3 inches higher up than they used to be so I was going to trim the canopy and move everything down a bit. Right now the bottom of my 250W MH bulb is 10.5" from the top of the water. It is a mogul base bulb and no glass shield between the bulb and water, havent had any problems with water splashing on the bulb in the last few years. I want to lower the entire canopy 2.5" which would put the MH at 8" above the water. Is this way too low? What is average height everyones MH bulbs from the water surface?

[Reef69]

I heard 10 in. is good, mine are 8 in. off the water surface, havent had any problems..

[::pete::]

8" - 10" is actually the recommended height so I dont see a problem with it. As for splash that would depend on your set up and inhabitants as well as you being careful. Others have put them closer @ 4".

[Richard]

I have mine about 6 inches off the water. One thing to remember is the relation between light and distance is an inverse square. So if you increase the distance from 5 inches to 10 inches you reduce the amount of light at the water surface to 1/4 of what it was at 5 inches.

[Ram_Puppy]

by lowering it, you may also reduce the coverage area as well, not sure if it will amount to much difference though.