MH Options?

I just bought a used 75 gallon acrylic tank with sump, lights (1x250W Metal halide on an m58 Spartan magnetic ballast and 2x24" T12s) with 50lbs of coralline covered live rock and 2 inch bed of live sand from a very established tank. It was a really great deal, but the GE MH lamp that was in it (ARC250/T/H/960) doesn't work. However I can't find anywhere to replace that particular bulb, so...

Firstly, should I even be putting the MH on presently? I'm not sure how much my cycle will be shortened by beginning with fully established live rock and sand. My goal was to purchase a large anemone with a pair of clown fish from the same woman I had the live rock from, after my parameters were in order - but I figured I would want my lighting fully up and running before I did that.

I am not averse, in the least, to waiting months before I put any more life in the tank - I want to take things as slowly as necessary, and no faster.

Secondly, when I do replace the lamp, what are some good options? What sort of color temperature should I be looking for, if I've got 2x20W Coralife 20k 24" T12's in there right now - keeping in mind that for at least a few months all I'd like to keep is one anemone and one or two fish (if possible)?

I'm trying right now to absorb as much information as possible, so any answers, corrections, advice, or constructive abuse would be tremendously appreciated!

 

First off kudos for being willing to go slow.

Secondly, you don't have to get the exact same bulb just make sure that it can run on a magnetic ballast. If you want more info PM Tangster, he's reall helpful with this stuff.

As to your bulb color spectrum you say the fluorescents are 20K? Are you sure? Either way, since you have some actinic supplementation going on I would get a 14 K MH bulb. Most people find the 10K and below to yellow and there seems to be a general consensus that there isn't as much coral growth under 20 K.