One thing to note - Tangs are a poor choice for this size tank. The general recommendation for a Tang (even a small one), is a 4-foot tank at a bare minimum. A 125g or 180g tank is usually recommended. Tangs are avid swimmers and grazers, and will quickly succumb to stress in a too-small tank.
Ich can often be brought on by stress, and Tangs are generally the first of most fish to fall victim to Ich if it is present.
dont think it is overcrowding b/c the most i have had in the tank at one time was 5 fish. My two damsels (who are still alive), a clown, a yellow tank, and a Lipstick tank.
Having come from a FW
environment, you'll have to forget everything you learned.
The general rule of thumb for SW
is 1" of fish (not including tail) for every 5g of tank capacity. This is a general guideline, and has some flexibility, but I wouldn't attempt to bend it much until the system is mature, and you've gained a lot of SW
I'm not trying to be condescending, just trying to save you some frustration - Ich can be one of the worst things in a SW
tank to have to deal with. Nuisance algae is right up there with it.
Your corals (and other inverts) will not be happy with this level long-term. 1.022 is barely above brackish water. Coral reef animals (corals, invertebrates) need a level of 1.025 - 1.026 to thrive. Make sure, however, to bring it up very slowly - over the course of a couple weeks is best.