Hello I'm new to the forum. I have been keeping fresh water fish for a few years and decided to start a saltwater aquarium a little over a month ago. It's a 20g with live sand, and 20lbs of live rock. Running with a filter, protein skimmer, heater, and 1 power head which will become 2 once in ready to add corals. Currently I have 2 blue/green Chromis, an emerald crab, and 10 turbo snails. Looking to get a pair of clowns and maybe one more small fish. Looking forward to any advice people can give me. Thank you.