I have collected Odonata (dragonfly) nymph from a pond. I try to feed this insect with Tenebrio molitor larvae as daily natural diet (one larvae per day). Based on your experience, what is the best natural diet for this predator nymph?
Dear Candra, based on my experience, everything that was swiming with the nymphs in the original pond was a potential prey for this predatory larvae. What matters is the actual size of the prey, should not exceed too much the size of a predator. I suggest any other non-predatory aquatic insect larvae together with maybe some crustacenas (Gammarus or related) should be suitable.
Chironomid larvae work great as well. They vary in size, so depending on the size of your nymph you can choose larger or smaller ones. I've found that dragonflies prefer these over mosquito larvae, which stay at the water's surface. Otherwise, amphipods are great for larger nymphs, but from your picture it looks like yours is perfectly content eating Tenebrio!
The non-predatory invertebrates present in the pond, smaller than the dragonfly larva, are a suitable option: larvae of chironomidae, non-case-bearing caddisflies, mayflies... also oligochaetes, amphipods. Dragonfly larvae can eat preys bigger than itself, and frequenly prey on tadpoles (the preys of biggest larvae of aeshnids including small frogs), but in a domestic aquarium freshwater insect larvare are the better option, but I dont think that that dragonfly have problems with Tenebrio molitor larvae.
Besides Tenebrio molitor larvae, perhaps mosquito larvae is a good option, because I can find it easily. But tadpoles is interesting to try when my predatory pet is getting bigger.