my cucumber sinks! i slice it about 1/2 inch thick, chop in halves, cook it for a few minutes & then freeze it, i chuck it in the tank & it sinks within a few minutes, peas & beans i dunk in boiling water for about 30 seconds & thats it, apart for shelling the peas, raw spud i just slice a thin piece, rinse under the hot tap & chuck in, bn's like it better that the pleco at the moment.