Personally, I prefer a stand alone frag tank, that way you can keep pests and diseases away from your display tank. If you're going to be in the market for a tank, take a look at aquaticeco.com. They've got an 8 foot trough for like $300 shipped. It's not a conventional tank, but you can get some top down viewers online for like 20 bucks a piece. Not only that, but you get more volume and all you'd need is an in sump skimmer. Just run the skimmer on one side of the trough along with a few strategically placed powerheads and some lights and you're good to go. I'd like to recommend the reefbreeders Value LED fixture. I've used it on several tanks in my time and have had great success out of it. One light worked over a 40 breeder for me so depending on the types of frags you'd like, I'd say one fixture would be good for a 36'' spread so long as you get the 120 degree optics. You can also use hang on the back media filters to keep water parameters in check.