I have an open-top shallow tank I have made into sort of a mini-ecosystem. Since it's shallow, there's a big, tangled clump of driftwood sticking half out of the water down one end. Until then, the wood had been submerged, and currently it's got a healthy colony of some kind of fungus, as well as a thriving population of very tiny insects.
The fish in the tank spends most of his/her (not sure if it's a plakat male or an aggro female) time hunting around the wood and rocks. But it wasn't until recently when I switched on the light that I noticed how many creatures had made themselves a home in my tank.
There are heaps of gnat-like insects on the moss and emersed parts of the wood, along with dozens of microworms on the submerged sections. There are even a couple of little centipedes that pop up every now and then, and seem to be quite happy living in the cracks and crevices.
Unfortunately, my camera can't zoom in enough to get a focused shot, but I included a couple of shots of the tank as a whole, and one of my female/male so that someone can tell me what gender of fish I have.

Is this fish male or female? I have been calling it a female, and it's name is Brighid, but the general appearance and personality makes me think she might be a he.

A full tank shot. The water isn't quite that dark, but last time I checked the pH was hovering at about 6.0. However, surprisingly enough the tank is fully cycled and remains so even if I miss water changes for that week.

Blurry moss shot. This is just some moss I pulled off the wooden sleepers in my mum's garden. Just today I found some moss that sprouted up overnight, and it was growing in the exact same way as Christmas moss. I've taken some to hopefully try and grow when I set up my wild betta tank.