Metal halide light question

[airbrnebkr]

I am looking for a Metal Halide light setup. I have been looking at some complete fixtures on Ebay that look pretty good but I don't know. Does anyone know anything about these? How many MH watts would be good for a 55 gallon tank? Should I get a fixture with MH's and PC's or MH's and VHO's? whats the difference when combined with MH lights? I know there are a lot of questions here but I am new to MH lights.
Thank you,
Doug

[Guy W]

I'd check and compare prices at www.hellolights.com

as for combined fixtures, I'd go for that if you can. VHO or compact would be fine, but compacts take less electricity I belive, and the bulbs do last longer.

Why to get the combined fixture? because you can turn on just the compact or VHO bulbs for an hour before the big lights go on, and they can be different colors like Actinic, to simulate and dawn/dusk effect over the tank.

For a 55 gallon tank, I would go with 2 175watt MH bulbs and 2 48 Inch compact florescent bulbs.

that would give you around 9 watts per gallon of water, which maybe a little overkill unless you want to keep the most demanding corals. But with a 4 foot long tank (or is a 55gal 3 feet) you would want 1 bulb every 2 feet I think. But now that I think about it, if the tank isn't as long as I think it is, maybe another setup with 36 inch compact or VHO bulbs and one 250watt MH bulb would be better.

Anyways hope that helps a little.

[slipknottin]

I agree with Guy on most of his points.

You can also buy the CF or VHO and MH setups seperatly, then install them both in a hood you built, which is what alot of us do.

MH should be run on average every 2 sq ft, but it depends on your tank top bracing. The worst thing you can do is put a MH directly above a brace, youll get a large dark line down the center of your tank. Ive had to install two MH bulbs on a tank 30" wide beacuse it had a top brace. I could probably have sliced the brace off and replaced it with a clear piece of glass or acrylic, but the tank was still under warranty.

As far as the VHO vs. PC debate. Im partial to VHO. I find PC bulbs to be quite breakable, and that for me negates any savings I might get from the bulb running longer.