Observation 4

There are some immediate changes that are apparent in the Micro Aquarium this week. Firstly, the water level is even lower than it was last week (measuring up to about 1/3 of the Micro Aquarium). Secondly, there are many less rotifers in the water (from last week as well as overall). Their numbers have diminished from the hundreds to just a few. They are still moving: some are swimming, some have curled up, and some have latched onto small particles in the aquarium with their "toes", possibly in order to catch food moving by. They are also evenly distributed across the water in the aquarium, as opposed to the first week's observations when they were more heavily distributed in the scum at the bottom.

The spores that have been appearing over the last couple of weeks have multiplied also. Instead of just appearing here and there, they are everywhere, in every frame now, with approximately 500 spores per frame (4X objective).

There is also still an abundance of bacteria and protista life, most noticeably an increase in the cyanobacteria nostoc population, as they are everywhere now. In addition I have managed to locate another speicmen of the unknown cyanobacteria, many specimens of cyanobacteria calothrix, and one specimen of the amoeba protist (but not the other two protistas).

Some of these spores and microorganisms have persisted above the water level.

New this week is a filamentous development around the greenery added to the top of the aquarium 4 weeks ago, clustering mostly on the side of the greenery that is above the water level. Under the highest objective I cannot detect any organelles or different cells (they appear as long unbroken strings). Could possibly be a developing fungi.

In addition, there are also some clusters of small circles or sacs, that have the same coloring as the rotifer philodinas, that I noticed during the first observation, in the birdbath scum at the bottom of the aquarium. That initial cluster has been gone for a couple of weeks now, but this new cluster is located at the tip of some greenery at the top of the aquarium. Movement is uncertain, but since their coloring is identical, I think that they are alternate forms of the rotifer philodinas - either sleeping, or more likely in the reproduction stages before "birth."