t to the maxx2:
Im thinking of setting up a nano reef. I have had a few tanks in the past, and currently own a 45 gallon fresh with 2 oscars and a 65 gallon salt with a 3 ft eel. Im thinking setting up a 15 gallon or so reef, how much am I looking to spend? And any recomendations on equipment?
If you have to ask "how much am I looking to spend," you can't afford it
Seriously: For salt water (esp. reef!), the bigger the tank, the easier it is. Among other things, I've had a 29g salt, 120g reef (still going), and a 5g nano-salt for unwanted live rock hitchhikers. The critters from the 29g salt migrated into the 120g reef; the 5g nano-salt was taken down after the octopus died of old age, and converted to a betta tank for the spouse. The 120g is by far the easiest tank to maintain with the most stable chemistry for the least effort.
If you want a 15g reef, you're looking at a minimum of $100 or so on lights (pc, most probably; something like the coralife pc fixtures), or more if you DIY a hybrid pc/halide setup (though I've heard that with LED illumination, things might get interesting); and probably another $100 or so on a protein skimmer.
Ditto the recommendations for Bob Fenner's "The Conscientious Marine Aquarist." I'd also recommend "Natural Reef Aquariums" (John Tullock, if memory serves me right). John Tullock also has a relatively inexpensive book (Barron's publishing) where he describes setting up a 29/30g reef.
I'm a huge fan of live rock, and a very satisfied customer of Tampa Bay Saltwater's "cultured" LR.
For a regular (50g or more), both reefs.org and reefcentral.com have good fora. I believe either nanoreef or nano-reef (or some similar permutation) has a very nice discussion group aimed at 20g or less. reefs.org has a nano-reef subforum where members discuss their construction & progress on a nano.
That said, nanos can be tricky because your chemistry can go sideways in a hurry. And the evaporative losses must be made up daily (if not more frequently). But if you're willing to live with a single fish (or better, an invert only nano), your critters would probably be happy. A nano with just corals, algaes, cleanup critters, and shrimp colony could be interesting.
Finally, like all pets, you've got to make arrangements to have the tank fed, watered, etc. when you go on a (scuba) vacation!