Sounds like you have standard fluorescents, so no, they're not sufficient for coral, unless you have a lot of them, which is just pointless. Buy better lights. Evaluate what kind of corals you want first.
Ditto on the tang. You need to move him to a bigger tank. If you don't have one then trade him back to the LFS. Remember to research a fish's requirements before you buy it. You can get into a lot of expensive and heart-breaking trouble if you don't.
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55gal,216 watt Tek T5, 45#LR, 45#LS, 3 maxi-jet 900's on a natural wavemaker timer,phosban reactor, 5 gal fuge (built out of standard 10 gallon tank) with chaeto and feather caulerpa, sealife systems protein skimmer, wet/dry, 3 blue/green chromi, 1 skunk cleaner shrimp, 1 coral beauty,1 scopas tang, 2 false percs, 5 mexican turbo snails, assorted dwarf blue leg hermits, astrea snails, and nerite snails |