Are my Nitrates too high?

My Nitrate level in my community tank is 5.0 ppm is it safe to introduce inverts? my tank is SW, 60 gallons, live rock and sand. I own two damsels, one a yellow belly and one a yellow tail. I also want to add more fish, any advice? Oh yeah, and all other parameters are Ammonia-0, Nitrites-0, phosphates-0, PH-8.2, Alkalinity 161.1, and calcium of 400. I know the parameters are good, Exempt the nitrates,are they alright? I know they should be at zero. I have two other seahorse tanks, but I never have had a community tank before, HELP! What goes together?