candy cane or trumpet coral is an lps not an sps coral.
mixing the 2 isnt so much a problem , its just that leathers and other softies can shed and give off a mucus that would irritate some sps, like montioned carbon will help with this. alot of softies also like low flow while sps love a very high flow that would kill off alot of soft coral. soft coral also like a b it of nutrients that can brown out sps.
doing a mixed reef is actually easy i have sps, lps and softies in my tank like anything there are things to watch out for but def nothing to steer against completely
cheers