As some of you may know I have an issue atm with my 30G Cuckoo tank. This guy is in my 4ft tank with the Jaguars and tetra's and its a sterile tank (different equipment used).
There is no sign of any illness within that tank and tbh it's been my rock through all the hassle I have had with the other tank.
Anyway the LDA33 has always been since his arrival (2 months+ ago) always hidden from sight when lights are on and only coming out of his piece of wood when his cucumber is added to the tank.
Since Monday though he has been very active in and around the tank irrespective of the lights. Along with this he has not eaten for 3 days, though that maybe because I have been trying to change his food about.
He seems fine apart from this yellowing on his belly. Is this to be expected from a fish that has exclusively eaten just cucumber? Also I would like to feed him a wafer now and again, any ideas how to do so given whenever (lights on or off) if a wafer goes in the tank at least 1 of the Jaguars will appear and eat it whole?
I have thought about stuffing bits of a wafer into the cucumber piece?
Anyhow, enclosed a pic and would appreciated any advice about this (am not overly worried but wanted to just check)

Thanks