how high do you keep your MH's

[KyleinCT]

I am running 3x400 SE 10k MH's on my 210. Currently at 112" above water level and top of nearest sps is 6" below surface.

Looking for optimal light placement from others that run similar (PFO) fixtures!

 

[Myk]

112" really that seems very high.
I would run them about 8"-12" depending on heat issues.

-B-

 

[MikeG]

I am assuming you meant 12" and not 112", that is almost 10'. I agree with B, 8-12" is fine depending on heat issues.

 

[KyleinCT]

that would be a major oops, yes, one foot! How much pressure do you think, or benefit, is added per inch of drop closer to the water? when is too close?

 

[estubbaly]

that would be a major oops, yes, one foot! How much pressure do you think, or benefit, is added per inch of drop closer to the water? when is too close?

when your water starts to boil.

J/K

 

[vinny]

I run my M/H at 8" above the water and 4 4" fans come on with the M/H.

 

[ReeferMedic]

I have my 400s about 9'-10" from the water.