I'm putting together a new tank. Dimensions are still slightly in flux but it'll be something close to;
Width: 15-18
Depth: 20-21
Height: 24
~32-38 gallons

The tank's going to be for seahorses so I'll be a little limited on my choice of corals. I'm planning on zoas, gsp, xenia, etc but want the ability to host anything in case stocking plans change. I'm ok with higher items needing to be on the higher side, but would like to keep some gsp on the sand away from the rest of the rock. I'm thinking T5's or LED's to keep the power/heat down.

Assuming LED"s I was looking at this fixture.
http://www.ledwholesalers.com/store/index....p;productId=512
Would it be sufficient? How far up would I need to put gsp to survive in there? Guessing I could get away with just one of these.

What about for T5's? I was thinking maybe some of those new 12" ones from nanotuners. Not sure just how much wattage I'd need for T5's considering the depth of the tank.

Thoughts? Evil? :-)

That LED fixture should be more than enough for what you are looking at, but probably overkill in terms of cost. Considering that your setup will be low light, you could easily use PCs or T5s. If you went with the T5 route, the 18" T5s will be a better choice than the 12" for overall coverage. Ever thought about bumping the length to 24" to make it easier on fixtures? A 24" 4 bulb Nova Extreme would work perfectly at that point.

You should do a low light high feed tank, gorgonia, dusters, suncoral, dendro, maybe a few plants. Seahorses are beautiful they are just not very aggressive eaters IME. Get some nassarius or some other good cleaner.

The tank size is being dictated heavily by the space available. Looking like it's going to be closer to 18-19x20x34 atm. So might be able to get away with 18's along the width. I'll know in about a week.

The main reason I was leaning towards LED's was long term cost. With changing out bulbs and such every year on T5's and the wattage requirement I was guessing it was going to cost more in the long run than with the LED's. Is that not the case? I live in California where electric is kinda nuts.

Problem with PC's is heat. Need to keep this tank below 85 so the less I have to chill the better.

I could do low light, it's just that at the moment my tank is forced to do low light because of only having 20w pc's in there. Zoas and such survive just fine, but they don't thrive. With going through all the effort and cost associated with a new tank I'd like at least to have the ability to put a bit more in there and know that it's going to grow vs just live.

I have a pretty good clean up crew (including nassarius snails). I also have some seahorse safe hermits and sexy shrimp which do a good job of picking up the food the seahorses miss.

Related question. If I went the T5 route what wattage would I need? Most tanks I see on this site aren't 24" deep.