adding one more fish??

hey everyone I just wanted some opinions about adding one more fish to my tank before I actually do it. A little background on my tank. Its a fluval m40 14g... Its established and has been up and running for 9 months. I currently have tiny black onyx clowns in it and that's it and just some soft corals. I'm wanting to add a little clown goby. Water parameters are fine and I'm very good about my water changes (25% every sunday).. Do you think that having 3 fish in my tank would be too overcrowded and have a high bioload? thanks for the help.

http://ift.tt/1ZBDdcG