Ive been seeing these really tiny whitish colored bugs on the substrate of some of my cages. The only cage I haven't seen them in is my bearded dragon cage which is the only one without coco fiber. Ive seen them by my box turtles, crested geckos, pac man frog and whites tree frog.Their not on any of the animals and I really hope they are harmless. My science teacher told me they were fruit flies but I'm not sure. I only took one good picture of it. Its the little speck thats kind of oval shaped. Oh and sorry if I didn't post this in the right spot, i wasn't sure where it was supposed to go.