Observation 4: (11/3/2011)

Today, I noted that there was a tremendous increase in the amount of living organisms in my microaquarium. The numbers of each organism must have at least quadrupled. Upon initially viewing my microaquarium without a microscope, it appeared as though algae of some sort had begun to grow on plants A and B. Like before, my microaquarium contained euplotes, vorticella, and diatoms. However, I found two additional variations of diatoms and a new ciliate within the aquatic environment.
The ciliate, Blepharisma, is known to consume the bacteria that result from dead vegetation (Hanna 2004). Although there were only two that I saw, their presence indicated the decay that was occurring within my microaquarium from dead organisms as well as Plant A and Plant B. The two additional shapes of diatoms that I noticed were square shaped and round with an outer rim that took on the appearance of a star bursting (Sarconid Actinosphaerium). There were well over 50 different diatoms and contrary to last time, I noted movement, namely in the pennate diatoms. The diatoms moved very slowly, appearing to float. 
In regards to the distribution of organisms, I noted that there was a variety of organisms near the soil layer of my microaquarium. Also, where the plants appeared to be brown and in decay, concentration of organisms was greater. This is probably due to the fact that several of these organisms feed on detritus.

References

Hanna, Jannette. Nov. 2004. Blepharisma. http://www.microscopyuk.org.uk/mag/artnov04macro/jhblepharisma.html  Accessed 2011 Nov. 7