i have had alot of crickets but most the ones you get in bulk places are usually inbreed. which i think leads to sudden death becuz the crickets i get at my local pet store lasted me for like 7months and they were almost full grown when i get them and i had alot of em. they all died cuz my heater broke and they froze during winter. :/ however the crickets i got with my cham that were from lllreptile(idk where they get them from) started dieing like crazy i went from 200 to like 40 with in 3days and myset up was the same one i used for my other crickets. i think it has to do with the species of crickets i know i have kept wild ones alive for about 5months. iv heard of tophat crickets having softer exoskeletons that lead to more parisites spreading faster. try getting wild crickets while thier still around and raiseing your own. the cage above is perfect but u dont even need a vent on the side unless your keeping tons of them and they will chew their way threw even glue. also i feed my crix rabbit pellets becuz crickets eat the same diet as rabbits when thier in the wild and everyone says that in the wild animals are healthy becuz they naturally know what they should be eating. also cut back on fruit and vegies they spread bacteria fast i gave mine a slice of orange and a slice of potato once a week. also along with rabbit food i added dry oatmeal. they LOVE IT!! anyway i would suggest changeing where u get crickets from or try getting wild crickets. (usually the brownish colored ones idk what species they are lived longer for me than the lighter gray colored species)