My Julie Cories have disappeared!!!?

does Fisher Nick torious for disappearing in coming back but a lot of times in case is that I've seen it will disappear and never come back in about a year later you'll find ur dad courses under something if I were you before they die I would look under all the gravel and clean out your fish tank make sure you don't use chlorinated water use distilled water from a can but be on the safe side use gloves because you don't want to get your oil on them if you actually find the fish put him in an isolated tank and wait for him to recruit normally they usually disappear because something went wrong are they got sick I hope all is well for him good luck

What other fish do you have in the tank they do hide so have you checked ornaments plants behind the filter and heater .

Cory's also need to be in a group of 3-5 plus not just 2 on there own .