Nice tank you've got there. You've got a great start and that tank could look awesome if you work to keep it maintained.
I would start by getting a solid reef test kit. I use the API Saltwater test kit and the Reef Master test kit. You can buy it online here (
http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+4345+4452&pcatid=4452) (
http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+4345+15473&pcatid=15473)- Between these two kits, you will be able to test for Ammonia, Nitrites, Nitrates, High range pH, KH, Calcium, and Phosphate.
I've found that most of the trace elements can be kept in check by using a quality salt mix. I use Instant ocean reef crystals. By doing weekly water changes you replenish trace elements like Calcium and Magnesium.
The hair algae will probably slowly phase out once your tank matures. But to help it along, I would definitely consider some dwarf blue leg hermit crabs and some more snails. I like nassarius and nerite snails.