This is my 20long as less than 2 months ago.... more coralline now...
basically a FOWLR
It's got 2 misbarred B&W ocellaris, 1 yellow assessor basslet (pic was before), 2 peppermint shrimp (pic was before), 1 tongan fighter (LOL), 6 astreas, 1 BIG turbo snail, 8 nassarius snails..
On the back is a CPR aquatics aquafuge 2 w/skimmer, chaeto, 2x9w coralife PC, 2 koralia nanos, MJ900pushing through a miniarctica chiller (pic was before I hooked up the chiller to the pump), 150w coralife aqualight clampon with giesemann megachome coral (this bulb is white and expensive, I wouldn't buy it again without tons of actinics.) 50w stealth heater in aquafuge.
25lbs of liverock, 1-2inches of sand.. it varies.
BTW this is obviously a cellphone pic lol.