comments:
I completely agree that 4-5” of substrate is ideal for these kind of enclosures. I don’t do a gravel bottom, but I do kind of a lasagna layer of substrate with alternating layers of sphagnum moss, leaf litter, soil, and coir. With sticks/bark stabbed through to create passages between the layers. Fly, or mosquito, dunks comes in many forms, but it’s a media inoculated with a bacteria (Bacillus thuringiensis subspecies israelensis (Bti). ) that’s highly specific to flies. The larva (fly maggots) eat the spores of the bacteria and they produce toxins in the naturally basic digestive tract that kills them. It helps control fruit flies and fungus gnats by preventing development from larva to reproductive adults. It’s completely safe for non-flies. I like using this because it comes on granules made from corn, which the isopods and springtails happily munch away on. Here are some pictures of one of my typical bins.