To be honest, I was really thinking about a box that could handle the following: transport of 30 or 40 bass all under 18", 100 or 150 large bluegill, loads of golden shiners (maybe 5,000 or under)? This isn't a whole-whole lot of fish, but not small either. I love the boxes, by the way, pretty cool website. I haven't been able to figure out the volume for each box yet, but am looking. My guess is that the larger boxes range from 200 gallons, on up...