2 175w on a 55gal

Should I hang them? Do I have to hang them? They are 12 by 12" so how high from the water would you recommend hanging them? Would I need a fan in each fixture

 

I used to have mine in a hood about 8" above the water line. As long as you have good cooling on the lights, heat should be no issue.

If you don't use a fan on each of the fixtures, you will most likely need one blowing on the tank itself.

 

Okay thanks, what kind of fan could I have blowing on the tank itself because that would be a lot easier, also what kind of top do you reccomend for my tank? Should I use acrylic of eggcrate or somthing

 

Also, how far apart on a 4 foot tank should I space them? Thanks in advanced

 

Sorry I missed the followup questions....

As for the fan.. Any standard clip on fan will work perfectly. Can be had for $10 at Wal-mart. You could spend more for something that looks better, but most people don't.

As for the spacing.. Each Halide bulb normally covers a 2' square area, depending on your reflector of course. If you space them 2 feet from each other, centered in the tank, it should cover everything well. I would start there and see how it looks. You may find that you want to move then a little closer to center. This would leave you a little dark on the very upper edges, but this is a very minor issue for most.