For a 72 gal
I would go with two MH
lights. Three would put one MH
lamp directly over the center brace therefore rendering it pretty much useless. Brenden is correct that MH
cover about a 2x2 area so two in a 4ft tank will be just fine. As far as wattage goes, it really depends on what you plan to keep. There is really not a lot you can not keep with the 4x96watt CF
. Stepping up to MH
will allow for more SPS
corals and clams. I just purchased a MH
fixture from www.aquatraders.com
and am happy with it. If you are not a DIYer, it may be an option for you. I got the 2x175watt MH
with 2x 96watt actinic. As far as bulb K
goes, it is really a matter of personal preference. 20K will give you a crisp blue shimmer to the water while 6500K or 10,000K will permote the fastest coral growth but will look more yellow, so more 03
suppliment may be needed.
where would you put a clam with this setup. About a 5ich super crocea.
The corcea is a rock dwelling species so it should be kept on the rock work. Find a flat spot for it to attach and make sure there is plenty of room for it to open, expand and grow. It can be kept in the sand bed as well but I recommend burrying a flat rock in the substrate for it to attach to.