I've had my flame scallop for almost a year now and he's still doing great. I've never target fed him, but I do feed multiple times a day. I run a skimmer and UV sterilizer, but I have to assume that he's getting what he needs from the multiple feedings (I change it up throughout the day - flakes one time, pellets the next time, frozen the next, etc...). I'm not implying that you shouldn't target feed yours because it could be a case of me being one lucky gal that mine has made it this long DESPITE me not target feeding it.
Good luck!