Dragonfly Nymphs in aquarium

The first time I got a dragonfly nymph in my aquarium was by accident.
This accident took me on an amazing adventure through which I learnt about dragonfly nymphs.
My whole family enjoyed following our first nymph development.

Nymph Eats Fish

Nymph molts

Dragonfly nymph encounter

Nessie reveals herself - black saddlebags skimmer

Dragonfly larva in aquarium

What bug is that in my fish tank?