Hello, and thank you for your inquiry! The Kobe Bed has a distance between slats of 6" between each slat. There are a couple of solutions to this, one is a product called a bunny board. It is a thin mattress foundation that is generally about 2-3" tall and creates a flat surface for the mattress to rest on. Another option is to cut plywood to fit the bed frame if you prefer the mattress to be lower overall. Also, the Kobe Bed can accommodate 400 Lbs.

Hopefully this helps!