i have a sailfin Gibbiceps and on numerous occasions tried to put zuccini (courgette) thinly sliced and slightly boiled (and at first raw) in the tank for food (tied to a rock or bogwood, of coarse). i was under the impression that he would litterally gobble it up in a night but he seems to avoid it, i have seen him go near it (but not touch it) and then ignore it. He is only about 8cm long.
my tank parameters are great and i have other hapy healthy fish in the 4ft planted, tank with him.
i have only had him for about 8 days.
cheers
Jordan