It would be a good idea to do a few water changes to see about getting the nitrates down some. Below 10 ppm
is a decent goal for a new tank, zero being ideal but not necessary. Fish and mobile inverts will tolerate the nitrates for the most part without issue.
As far as corals are concerned, most softies are quite tolerable of nitrates to a certain degree. You should be safe to start adding hardier leathers, colts and shrooms
, mabye even some less exspensive zoo's.
General rule of thumb is once the tank is stable, softies at about 3 months, LPS
at about 6-8 months and SPS
and clams after about a year.
What type of lights do you have?