Banana Worms (Panagrellus nepenthicola), are prolific small nematodes that are great for feeding the small fish fry. Banana worms are not the same organism as parasitic banana nematodes (Helicotylenchus dihystera) that are known to infest banana tree roots. Banana worms are slightly smaller than Walter worms and Microworms. They measure at 40 microns in diameter and 1.5 mm in length. Despite their small size, they are one of the most prolific nematodes. While banana worms sink in water, their lighter weight allows them to drift in the water for a longer time before reaching the base. Very little effort is required to culture Banana Worms. While accepting of a wide range of temperatures, the optimum yield will result from 20°C to 27°C.