Ok so I have a 22gal tank that has had two per ups clowns in for around two weeks and I’m getting some snails and hermit crabs today I was wondering if I could get another fish today aswell like a royal gramma can I get the snails hermits and royal gramma today or not ?i also need help deciding if I want a royal gramma or a different fish but I’m 95% sure I want the royal gramma (the filter has just fell a little but is still in place I’m going to move it today )