Not sure what you mean from this but it is far from helpful adive.
plan on having Tangs,Butterflies,angels, and eventually clowns.
that is an abitious list, even for a tank of that size. Sounds like you want a FO
(recommended) tank. The next step is to pick out one or two "must have" fish and build the rest of the livestock around those. I would actually add the clowns first and the tangs last as they are the most aggressive. Please post a list of desired species so we can help more.
I currently have 20 damsels to cycle the tank.
Cycling with fish is a bit out-dated but most LFS
still advocate this method as they can sell more fish that way. There are two main problems with using damsels...1) it is very hard on the fish and most will not survive the cycle due to the toxic conditions and 2) they are very hard to catch and get back to the LFS
once the tank is cycled and you decide you do not want them. They are very aggressive and will go after even the largest tank mates. There is an article on "fishless cycling" in the Articles section at the top of the page you may find helpful.