Presonly i'd think a fox Face may get too big, but (dwarf) Anglefish, some butterfly fish, and maybe a dottyback(though there small there going to put up a fight and a loinfish wants an EZ meal not one it has to work for).
Thanks kreblak and Mandairn for your replies. Regarding my cycling question, I also learned quite a bit from this post, and am linking it from here so that other newbies can find it more readily. Corax has some good information there. Thanks.