Need A Mh Expert!!!!

[nu2salt]

hi....
i have came across 3 400 watt mh's that r retro fit and i would like to but them on my tanks. the problem is that they r a 55 and a 75 gallon tank. i know i will have to build my own canopy's for these. my question is how high do i need to make they canopy for it to be safe for the tanks.

 

[hot883]

I personally think that is to much watts for either tank. I would go with a 150-175 on the 55 and a 250 on the 75. There are a few on here that go with that much light, but am thinking not alot. The reason i know of is heat.

 

[nu2salt]

hot... i know heat will be an issue. i have 2 four inch fans i can put in the canopy on the ends. maybe i should let you know that these lights r highbay warehouse lights that i am gonna remove from the fixture.they r true mh's not high presure sodium. can i stil make them work if the canopy is high enough? and if i can what height would you suggest?

 

[nu2salt]

also hot if you don't think they will work for what i have do you think if i posted them in the classifieds if some one woukd trade out for i truley need?
if i explain to them what they r

 

[007]

heat will be a big problem for you no matter how high of a canopy you build. The only way I forsee you being able to avoid heat issues would be to mount the lights as pendants from the ceiling with an open top.
As for selling the items, you will be able to get some money for them, but not much in comparison to an actual aquarium fixture.

 

[nu2salt]

thanks guys i'm in the process of posting them in the classifieds along with some other stuff.

 

[scsinet]

You'll be better off to find a local reef club and see if someone will trade you for a smaller fixture. 400 watt high bays are usually pretty sought after in the aquarium world because people generally are upgrading more than they "fall into" the big stuff.
You're better off as well... because you'd have to put them so high that you'll be discarding most of the usable light, which will end up being wasted electricity. Any difference in what you'll have to pay (between selling what you have and buying a smaller fixture) would have been eaten up in power usage and HVAC costs in no time.