with that size tank no wonder they look small. lol they looked small in my 75 when I started!! Keep testing your water levels but it sounds like your tank is off to a great start. I would wait untill you see some corline alge (red, or purple) growing on your glass before adding adding coral if thats were your headed. You could SLOWLY add some bigger fish in a couple weeks if your levels stay low, but if youra newbie, like I, watch what you get, you may not like it in the long run and trying to get them out is alot harder than putting them in