My run has all-purpose sand in it. The grains range anywhere from fine to very coarse (mostly medium). I've encountered a problem where my old cat scooper can't pick up small dried poop pieces (pieces because chickens step on it every so often and mashing and breaking it up) and and just falls through the holes. I haven't bought the reptile sand/bark scoopers because the netting is too fine and it would trap alot of sand in addition to the poop which isn't acceptable either. The reason why I am trying to find a fix to this issue is because I believe if this keeps happening, there will be accumulation of these missed poop pieces over time, and the sand in the run will have alot of tiny poop pieces. Does anyone have anything between a reptile sand scooper and a cat scooper in terms of being in terms of being able to filter sand? Or if anyone has a link to a cat scooper that has somewhat fine filtering slits that would work too. What a pleasant topic, huh?