Carol - I keep 500-1500 at a time. To clean I dump the crickets into a cricket keeper, big Tupperware or mixing bowl (just something they can't climb), dump the frass and fill the bottom of my box with warm bubbly water for 10 minutes. Then rinse it out an it's good to go. I don't keep anything on the bottom so it's super easy. And I pretty much never have escapees during transfer. Only clean it out every few weeks or as needed. Very low maintenance. 
