While using the commercial Crab traps, I noticed many times my bait would be gone without a lot of crabs, this is while using my NJ nets where I noticed the holes on the bait holder were very large.
I had some official commercial nets which produced a lot more. I noticed the openings in the bait holder where smaller and the bait would last longer. Those nets trippled the amount of crabs that were in my other nets.
Go to the hardware store and by a roll of very small mesh. Cut and mold into your bait holder. This will prevent the crabs from eating the bait, so they swim to the top and more crabs will enter as the bait is untouched.
If the mesh is too big, the crabs will stay at the bait pen and eat the bait till its gone, then move to the upper part of the net, but no other crabs will enter due to NO BAIT.
This will also prevent any fish, turtles, and eel from eating the bait.
The most I go with an overnight soak is 35 crabs om 1 pot.