Week 3 of Observation

This is the week after food was added to the Microaquarium. There were several population changes to note this week.

There were many more rotifers, particularly Euchlanis. I also noticed a good increase in population of Tachysoma. I noticed at least 3 Vorticella, the largest population yet. I saw another gastrotrich that looked like the one from week 1 observation. The gastrotrich still evades identification. I also noticed 3 or 4 amoebas, the largest number again. Like last week, there were incredible amounts of diatoms. One type was organized in a long filamentous shape. 

Image 1: a diatom, Pinnularia nobilis, as identified from Turtox Class-Room Chart: Diatoms, Figure B. This was the only structure like this that I saw. I could not find any literature as to why the diatoms were like this, if they did this on their own, if they formed their own sheath or inhabited an empty shell left behind by some organism. 

There were a couple of new organisms I identified this week.

Image 2: Difflugia identified from Free-Living Freshwater Protozoa: A Colour Guide, p. 95, Figure 186. I only saw one of these.

Image 3: Asterionella as identified from Pond III: Photosynthetic Microlife. I saw several of these diatoms. Not all had 5 cells; some had less.

Until next week.