In my 12 gal JBJ I have
3 X Pacific nerite snails
1 X Astria snail
1 X Persian conch
2 small Blueleg hermits
2 sexy shrimp
1 porcelain crab
1 pistol shrimp
We have the same tank as you..
5 red legged hermits
3 Astria Snails
2 peppermint shrimp
1 small pencil urchin...he does a great job cleaning!
Hope this helps!