min. tank size for a pair of larger sp. SH is about 29 gals.
i use LR (mix in some branchy pieces if you can), live macro, and about 1" of #3 aragonite sand. depending on how you set the works up, 5x turnover is good, but can be considerably more with creative placement, splitting, and alternation.
tropical species should be kept between 68*F to 74*F.
as for corals, softies, smooth mushrooms, and polyps are the best choices.
finally, buy true CB specimens from a reputable breeder or hobbyist/breeder. they will be disease free and come to you eating frozen mysis.