Distance between lights and tank

herbert4

Member
I am building a 125gal sw tank. I want reef/fish. I am going to hang the lights from the ceiling in a hood. I am wondering if its ok to leave open space between the tank and hood. If so how far and is there a maximum distance, I know there is a min because of heat. Eventually I want MH and VHO or PC (not sure yet). It will have to evolve due to $$$ issues. Any input on distance issue?
Thanks
Kirk
 

von_rahvin

Member
if you are doing MH lights they need to be atleast 12" away frm the water surface. also think that you are going to need cooling fans for the lights or a chiller for your tank. with VHO and Pc's you do not have to be that far away from the tank. honestly i would choose a combo of MH and VHO. I am currently upgrading my lighting to be 3 MH 400 watt 12k and 2 VHO 160 watt actinics. I am currently running just 4 VHO 160 watts. after i saw some of the tanks online that talk about the wonders o having a mh lighting system it sold me. the tank just looks so much better.
 

reeferx

Member
Cool project.
If you search, you will find a lot of old threads on this.
Assuming you go with metal halide, most people on here say 8-10 inches above the water.
But this is what I did: I took my pendant, aimed it at the wall and pulled back till I had something a little less than the diameter of the tank. This ended up being a little higher than the above rec. and worked great. I didn't have a glass top and didn't have any major heat issues. Of course I had more evaporation, but I had a five gallon reservoir on a float switch that compensated for this. You can still use a glass top, just know that it will take away some of the light, esp. if dirty, and trap heat. So use some fans if you go this route.
I have never used VHO, maybe somebody can help you with that option.
Good luck!
Matt
 

herbert4

Member
if i use pendant MH's are there any combo systems to incorperate VHO of do i need to skip the pendant and get a combo retro kit?
Any body know?
thanks
Kirk <img src="graemlins//evilwhorn.gif" border="0" alt="[Evil Horn]" />
 

dburr

Active Member
If you go with PC lights, my canopy is about 3" from the tank. Just enough room to get my arm in there. No heat problems, no fans.
 
Top