Nymph molts

A dragonfly nymph stays hours in one spot waiting for prey.

It moves to a new position a couple times a day.

Nymphs in my aquariums

February 18th 2017

 Some days, and even weeks, I don't see any of my nymphs - they prefer to hide. 

Dragonfly nymph encounter

November 25th, 2016

 I found this nymph in my aquarium a month after I got some water plants from the lakes of Central park of NYC.
 Apparently, it hatched from an egg I did not wash off from the water plants.

Nessie reveals herself - black saddlebags skimmer

In the third week of November I spotted Nessie (my dragonfly nymph) resting on the roots of peace lily.

Dragonfly larva in aquarium

It's very hard to spot a dragonfly larva. 

I don't see her for days and weeks. 

And then she shows up. 

What bug is that in my fish tank?

I give my fish tank a thoughtful clean up at the beginning of each season (every 3 months). To my surprise, during the last cleaning I found some kind of water bug hiding at the bottom of the tank. It's green. It has big yellow eyes. It has 6 legs. And it has a pair of something on its back that looks like short wings. An under water bug with wings?