I had a blue tang in the 29g for about a month, but when I transferred her to a bigger tank (55g), she passed away.
Our local fish store suggests that we only have about 2-4 fish in a 29g tank and they all should be rated for 55g or less OR they should be smaller than 4-6". Here is a great website to read about and buy saltwater fish, corals, inverts, etc.
http://www.marinedepotlive.com It gives lots of info on fish and says what size tank is ideal for them.
For algae, you should get lots of little hermit crabs and snails. We have at least 15 of each. We also have a sand sifting sea star (starfish) that eats the algae on the surface of the sand.