How to Keep Bait Alive
Special containers are made for most kinds of live bait, and you should use the right one. Most live bait does better if kept cool and out of the sun. Storing live bait for long periods of time is a lot of trouble so plan on using your bait soon after getting it. It's much better to get fresh live bait for each trip rather than to get a lot and try to keep it for a several days.
Keeping Freshwater Bait Alive
Live earthworms in the refrigerator may not sound too appetizing, but a cool, moist place is the best place to store them. Put the paper cups they're sold in into the refrigerator and they'll last several days. If you dig your own earthworms, put them in a paper cup with a lid — don't use plastic or metal. Paper will allow the soil to breath and not condense too much moisture in it.
Minnows can be kept in an aerated tank or a thirty-gallon plastic trashcan. Put an aquarium aerator in the bottom of the trashcan and the minnows will keep for several weeks. Drop a little goldfish food on top of the water if you plan on keeping them more than a few days. Take a few minnows out to use and leave the rest for later. If you're staying at the lake or have a pond nearby, you can use a minnow bucket with holes in it to let fresh water flow through.
On hot days add a few ice cubes to your minnow bucket to cool the water. Do this all during the day to keep them lively and healthy. Don't add many at one time; if you get the water too cool, they'll die when you put them into the warmer water you're fishing.
Crickets will live a long time in a good wire cricket box. Put a cut potato in the box with them each day for moisture and food. Make sure the box is in the shade, out of direct sunlight. A cricket box with a wide top and a metal sleeve allows you to take out one cricket at a time. You can use it while fishing and to keep them alive between trips. A wire tube with a stopper in one funnel-shaped end also works well, but it's more trouble to get a cricket out when you need it.
For other baitfish, a round bait tank is just about the only way to keep them alive unless you have a dock on the lake and can put a big wire basket in the water for them. While you're fishing from a boat, you can keep them in a bait tank or a thirty-gallon plastic trashcan, but you need to use a twelve-volt aerator or small bilge pump to keep the water circulating. Since most baitfish are open-water fish they need a big tank, and won't survive well in smaller minnow buckets.
Mealworms, wax worms, and grubs kept in a container of meal in the refrigerator will stay alive and healthy for several days. Leeches, salamanders, and hellgrammites can be kept in moist moss in a tightly sealed container with a few air holes. Crayfish need to have shallow containers of water that stays aerated. Wasp nests containing larvae need to be put in a paper sack and kept in the refrigerator, but be real careful when you open it because some may have matured and can sting you.
Make sure everyone in the house knows where you keep your bait in the refrigerator. Don't take a chance that a kid may open a bag with a live wasp in it, or that anyone may open the wrong container looking for a snack.
Keeping Saltwater Bait Alive
Saltwater bait is much harder to keep live and healthy than freshwater bait. Eels can be kept in baskets in the water but unless you have a place on the water to keep them, it's hard to manage. Most saltwater baitfish can be kept for a day of fishing in a freshwater bait tank or in the built-in bait tank on a boat, but most will not last more than a day or so. Shrimp and squid can also be kept in a well-aerated bait tank for a day or so, but you need a tank with fresh saltwater pumping into it to keep them alive for any length of time.
Sandworms and bloodworms will stay alive in the moss they're packed in if you keep them moist and cool. Refrigerate them just like earthworms and make sure they're in paper cartons that can breath; however, it's best to start with fresh ones every day. If you keep any leftovers for use later, don't depend on them.