Advertisement I was just wondering if there is any formula for figuring out if a feeder insect, in my case Dubia roaches, is too large for a tarantula. Most of mine are relatively small, the largest is my P. fasciata and that's only about 4" maximum DLS. The rest are 2.75" and under. I currently have a surplus of adult male dubias however and wanted to feed some off to at least the Pokie. Would these be too large for him/her?