LisaLQ
Fish Gatherer
Plecos like wood to nibble on, so try to put a piece of wood in you tank. Have a look also at the pleco forum here. It has a pinned article about plecos under 8' and other useful info on these species.
Good luck!
His tank isn't big enough for a plec - there's no point reading through the "plecs under 8 inches" thread as there's none suitable. Otocinclus would be an option in a few months, but apart from that, there aren't any plecs that stay small enough to go in a 35l tank.
Sorry to hear about your gibby. Just goes to show that even the hardiest fish can succumb to a cycling tank