I've taken a dip in the Bathhouse Pools three times and I've gotten crystals two of those times,, 3 and 8 crystals respectively. That was great, but when I went to turn them in it said I didn't have any crystals to turn in. Are they added to your total crystal amount automatically, or is this a glitch? Unfortunately I don't pay attention to my crystal amount unless I'm saving up for something, so I'm really stumped.

Yes they are automatically added to your currencies :)

all the currencies you receive from the bathhouse are automatically added to your currency bank! i.e. crystals, sbq invites, recycle points, etc :)

Phew, that's a relief! Thanks so much for answering my question, you guys!