i went to a couple different web site and there is a huge difference in price. for example, www.drsfosterandsmith.com 400 watt bulb was $129.00. at www.1000bulbs.com they were $16.00 -$32.00. whats the difference?
Price is going to range greatly between manufacturers, as well as color (kelvin, or "K
") temperature. The 400w MH
bulbs I could find on www.100bulbs.com
that were between $16.00 - $32.00 were all either 4000k or 4200k. You absolutely do not want this for a reef tank. This k
temp will make your water look extremely yellow-green. The lowest recommended k
temp for a reef is 6500k. Even with 6500k bulbs (we use 6500k Iwasakis), you will need a considerable amount of actinic supplementation to bring the coloration to a pleasing *white*.
I consider my tank color to be very clear/white. We use 3 x 250w Iwasaki 6500k's, and supplement that with another 640w of VHO
I'd say your "average" reef MH
bulb runs between $55.00 - $120.00. Again, depending on color temp & manufacturer.
what other parts do i need besides ballasts, fan?
Off the top of my head, you'd need at least reflectors.
If I think back, our MH
bulbs were $69.00 each. Ballasts were about $50.00 each, and Spiderlight reflectors (which included mogul sockets were $48.00 each).
There is a lot
to consider as far as MH
lighting is concerned. I suggest you sit back, and do some searching here, and on the 'net in general. Lots of considerations, and many are personal preferences.
A couple things to think of.
Wattage. Depends highly on what you intend on keeping. for a 30" deep tank, 400w is recommended. This is assuming you'd want to keep "everything" (sps
, clams, etc.), at all tank depths.
Color temp. I kind of summarized above. In general:
< 6500k -- you do not want for a reef
6500k - yellowish-tint, needs a lot of actinic supplementation.
10,000k - most "white"
20,000k - blue-ish tint.
Bulb life. If this is a consideration, research. Iwasaki bulbs have extremely long bulb life with little loss in par/spectrum. Some say 18-24 mos. Ours have been running 18 with no issues.
I've heard of some HQI bulbs needing to be replaced every 6 mos.
Intensity. As color temp rises, intensity is lost. A 250w 6500k bulb is approximately as
intense as a 400w 20,000k bulb.
Intensity = ability of the light to penetrate the water.
Just a bunch of stuff to think about. Lighting is one of the most heated debates in reefing, and is subject to many factors.