i have had this combo for over 3yrs
1st i had a very very nice FF with high dorsal fin the trouble is they grow so slow and the p14 got alot bigger than the FF and over powered it and sucked both its eyes out
i then got a 12inch FF from a freind this one was dam mean it attacked the rays and was even beating up a 22inch asian aro trying to suck his gil plate
i then got the one i have now and its fine with rays never bothers them it just fight with my ST at feeding time BUT i did have a problem when my female p14 was preg
it was strange it never sucked on any of the rays ever but 2 weeks before the pups were born it started sucking just on the lump were the pups were then as soon as the pups were born it stopped then the next time she was haveing pups the same thing
their was never any flesh damage just a slight off black color
i think i would take a very sick ray to just sit their and get sucked to death if you just keep a close eye on things its easy to see if the FF is sucking the ray as it get kiss marks on the disk
i sort of trained my FF as soon as he looked like he was going to suck i used to bang on the glass and scare him at one point i even chased him around with a net it got to a point were he knew if he sucked something bad was going to happen and he would stay at the oposite end of the tank to the ray if the ray came to his end he would swim to the other end
its not until they get to 8inch they are trouble below 8inch they are fairly passive
i know this sounds like alot of work but FF are like a liveing filter and it keeps my tank spotless their is no algue or leftover food EVER
i have made this sound much worse than it is try it you may get lucky if you get a FF that has grown up with rays chances are it will be fine just feed it well as once the FF has cleaned all you tank glass and pips then if it has nothing else to eat it may start on the slim coat i give mine lots of blood worm and spiralina flake basically they eat everything
FF are not like piranha they are not going to go mad and kill your rays over night it would take 2-3 weeks for a FF to kill a ray and if it did have time to kill the ray then you are not watching you tank and rays enought
