You can build a DIY worm farm that will produce worm humus and juice that can be used to fertilize your plants. It's simple to do and only requires three buckets, some kitchen scraps, worms of course, ...

For long-term nightcrawler storage, consider investing in a worm farm. Like all animals, nightcrawlers need to eat to stay alive. Well-fed worms are more active and will ultimately attract more fish.