To answer the second part of the question first -- no a 10-foot cast-net with 3/8 mesh – which weighs 12.5 pounds (1.25 lbs per foot) is not too light for catching bait in 3-to-6 feet of water. It will work fine. I have been using Lee Fisher cast-nets for over 20 years and they are excellent.
Lee Fisher builds three series of cast nets: 1.) The Bait Buster, which is their top of the line and has 1.5-lbs. per foot; 2.) The Joyfish, which has 1.25-lbs. per foot; and 3.) The Mako which has 1-lb. per foot.
Remember that whatever cast-net you purchase, make sure you condition it with fabric softener before you use it. After you condition it with the fabric softener, rinse the cast-net with water and get all the fabric softener off the surface of the cast-net. Most of the fabric softener will be absorbed into the mesh. If you don't rinse the extra fabric softener that did not get absorbed, your net will become very slippery and hard to hold on to.
Also once you throw it into the water to catch your bait and the water drips off the cast-net with the extra fabric softener, the ground below you will be very slippery. Be careful -- it will be like standing on ice! Whatever you do, never rinse your cast-net in dish soap (like Dawn). Cast-nets are made with monofilament, which is a petroleum based product. The dish soap which is made to remove oils, will pull all the oils out of your net. It will leave it dry, brittle and damage it, and it will not last long before it starts tearing.
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