I had the tank for 2yrs its a nano-cube24 from jbj. My nitrate levels and all the rest have been on point so far, just cant let up on the maintenance. I have a mini skimmer on back and i add a chemipure elite every few months. Really clears up the water, even makes it look hd. Recently i added a Viper K2 70w Metal Halide, the corals have began to adapt and are opening much more.
Regarding having too much fish in the nano, that was at the beginning guess all the exciting of the hobby. Now i have just the blue tang, maroon clown fish and a candy cane shrimp.