320g reef lighting help

[twist of lime]

Last weekend we picked up our first big tank, a 320g acrylic tank that is 72" long, 28" deep, and 36" tall. It also comes with a 75g sump and with all the pipes and stuff the total water volume is 420g. It does have a canopy. We woud like to make this a reef tank (we want to keep sps, lps, and softies) and we are deciding between 2 options.
Option #1-get 3-5 (how many should we get?) 400w mhs with 2 or 3 fans in the canopy.
Option #2- get 2 1,000 hms. Unfortuntly this will raise the electricity bill alot so if the 400s will work it would be a better option.
Which do you guys think would work better for this tank? Also which reflectors are the best. Any advice would be helpful.
Thanks

 

[dougie]

IMO option #1 will work fine, say 4 400w halides. because your tank is 3ft high, i would go for 10,000k globes to get good light penatration to the bottom. supplement with say a 4 80w T5 atinic to get the blue. id put any clams, sps, towards the top of the tank closer to the halides, and have the less light demanding corals further down. HTH.

 

[amay121]

3 x 400W MH. I think you can do this very nicely. I wouldn't go 4 though, well, not unless you really needed to.

 

[dougie]

your right amay121.over a 6ft 3 will do. im thinking its an 8ft. my mistake.