Finding air bed leaks and air mattress leaks
My personal experience (one air bed leak, one air mattress leak):
Inflate upside down (punctures are likely on the bottom or sides). Search visually for surface blemishes. Spray blemishes with soapy water and look for bubbles. Mark leaks with a marking pen, deflate mattress and repair leak with kit.
In my experience seams are well sealed and unlikely to leak (barring manufacturing defect).
Generalized soaking in soapy water works poorly because soapy water drains quickly from plastic surfaces.
I recommend inflating mattresses on a blanket or foam strip to cover sharp surfaces.
