Check out this fly trap. I am sure you could bodge one up pretty easily. I will look further because i am sure i have seen one made with two plastic 2 litre coke bottles somewhere. Most of the flies will drown but if you put it in the enclosure each afternoon there will be live flies ready to escape into your lizards' eager mouths
Rid-Max
Holds approx. 6,000 flies
7.5" tall, 7" diameter
Great for patios, camping, backyards, kennels, horse trailers. Used in restaurants, schools, and homes. (Assembly Required)
Safe 2 Use
a/k/a Fly Busters
800-931-9916
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