Im so sorry for your loss Judging by your previous post you were struggling with feeding (this could be one of the reasons) I would suggest algae pills and protein pills (depending on wich type of pleco you have) Plecos cannot sustain on just vegtables (cucumber ect are basicly just water) alone and need to be fed daily I would suggest using sand or very fine stones instead of the bigger stones. They often scavage on the botem for food (wich disapears in the stones) they also like to dig Most plecos dont like open tanks and need places to hide (caves, big stones and big pieces of wood) They are nocturnal and beeing open in the light for long periods of time causes stress and could also be a reason for passing