Ok, I apologize, but I forget how old Squirt is... is it possible that it is just metabolism slowing down due to age? How long since his/her last meal?
I have heard of people offering nothing but, certainly we have all heard of people trying that with leos to get them to eat mealworms in a bowl. I don't know if that is the right course because I feel bad about doing that to a gecko.
Guess you could always try to the new(ish) universal MRP with the flavors, I only keep one crested, I don't think they come in small bags and I'm not sure how long it lasts, but who knows.
I'm voting something is off, maybe your CGD is older than 6 months? Maybe you mixed it just slightly differently? (Ours can be that picky) or maybe just getting older.
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0.1 Albino Leo Gecko
0.1 Crested Gecko
1.0 Dear Boyfriend
Departed: Harvey and Spock