Either doses of chlorine (tap water with a bit extra from a pool supply bottle) or tap water with small doses of bleach, or just plain boiling for a period of time, if your goal is to disinfect. Generally speaking true ceramics have an extremely high melting point (1200 C), so I'm doubtful these would be harmed.
Vinegar is not a sure thing, chlorine or bleach is the way I'd go for chemicals. If you use chemicals, give it a hearty number of rinses afterwards, or if possible, just put the whole amount in a bucket under a spigot and let the water run through it for a good 30 mins or so.
If bleach is scary, chlorine will do the trick (adding some over the amount that is in the tap). In that case, dechlorinator will take care of that afterwards.
Sorry about your loss...I really like plecos.