The best technique to preserve feeder insects varies according to their type. This is a general guide: Keep mealworms and superworms in a shallow container with a vented top and wheat bran substrate. Provide a potato or apple slice for moisture. Replace both the substrate and the food regularly. Waxworms: These have a shorter lifespan and should be obtained right before feeding. Keep them in a cold, dark place (about 50°F) to inhibit their growth. Phoenix Worms: Place them in a jar with a vented cover and some moistened paper towels. Replace paper towels as required. Crickets: Place them in a well-ventilated container with egg carton pieces for climbing and hiding. Provide a water source and cricket food.