The things I have learned...
1. Take your time aclimating your new fish. Lost 2 little
green chromis this way inside of 2 days of introducing them to the tank. With my new clowns, I did a slow drip for 2 hours before putting them into my quarantine tank. One had a bit of problem for about 10 minutes but then started to get it's bearings.
2. Temp drops also kill fish. Lost another 2 chromis plus a snail when Atlanta got hit with cold spell (mid teens F) and the temp in the tank dropped about 5 degrees overnight (might have been more). Added a second heater to prevent that from happening again.
3. Diatoms are inevitable if you overfeed. I initially fed the chromis everyday and it was way tooooo much. Cut the feedings by about 2/3 and only every other day now. Oh and my nassarius snails love feeding time. They come out of the sand when food is put into the tank.