New Tank

I just set up a very basic 20G Long. have an aqua clear over top hang filter and t5 LED that I had with my previous 40G. I've added buffer, prime, and stabilizer. Anything else anyone thinks I can add. I have 2 Oscellaris Clownfish, peppershrimp, 2 Blue Leg Hermit, and 5 snails. Also have 2 Live rock with a dry rock as well that I added.

Just trying to get ideas of anything I may have missed

Thanks