is this enough lighting

[rayraypico]

100 gal tank just starting to cycle with damsels. i was going to purchase a 250 watt mh fixture. will this be enough to light up the tank. will it be enough to support live rock? or corals? what is the difference in the bulbs you can purchase their are 5500k 6500k and 10000k and 20000k obviously quality but what is the meaning of that

 

[alti]

what type of corals r u planning on keeping? you will probably need at least 2 MH's for a tank that size. u also might want to get some vho or pc bulbs so you can create a dusk/dawn effect before and after the halides come on and also to add a bit more blue color to the tank. the different in the K(kelvin) rating is the color spectrum. the lower the number the closer to the red end of the spectrum and the higher the number the closer to the blue spectrum. you need to use at least a 6500k bulb, but it will be pretty yellow and you will have to add some kind of actinic suppliment to make it more pleasing to the eye. 10,000k is probably the most white in color. i like the 12,000k since it has a nice light tint of blue to it. the 20,000k are pretty blue.

 

[rmckee22]

If you want to place coral in that tank, there is no way that bulb will be enough. I have a total of 384 watts (4 96 WATT pc bulbs) for my 80 gal and I would like a bit more. With that one bulb, that is only 2.5 watts per gallon WAY TO LOW for any coral. You should shoot for at least 4 watts per gallon (And I think that is low) so I would get another light just like the one you got that will give you 5 watts per gallon.
Also, I don't know what kind of Damsels you are getting, but I would not put blue damsels in for your first fish (Get Chromis). They are very territorial and will establish their areas in the tank and as soon as you add anything else, they will relentlessly attack them. I added 4 blue damsels for my first fish, then a week later I added 3 royal grammas & a blenny. The second I let them out of the bag they were like piranahs attacking the new fish. I had to take all the rock out of the tank to catch them (The damsels), then I took all of them back to the store except for 1. When they are by themselves they are fine. The fish that stayed in my tank was one of the worst when I had all 4 of them, and as soon as I took the other damsels out, he was totally mellow.