Observations for week 2 (10/27/2011)

     Upon observing the micro-aquarium without the aid of a microscope I noted that the water level had gone down by about 25%.  Also, the dissolving food pellet is still visible, and now is surrounded by some sort of brown filamentous growth.  I also noticed a few larger organisms in the aquarium, however I was unable to identify them without the use of microscope.
    Once under the scope, it became apparent that there were several minute changes in the ecology of the aquarium.  Utricularia gibba is beginning to show signs of death as multiple brown discolorations appeared on the stem of the plant.  Many of the digestive sacs on the Utricularia gibba have ruptured and are filled with some sort of filamentous, algae like growth.  The Amblestegium sp. has similar growth scattered across its stem, as well as a small amount of death at the lower right hand corner of the plant.  Regardless of these factors both plants show signs of new growth.
     Vorticella sp. seems to currently be the most abundant organism in the micro-aquarium.  Last week there were only 3 to 5 specimen per frame, but now they have reached up to 12 per frame.  Most of them remain anchored to the plants, however several now float around attached to sediment or dead plant tissue.  Some Vorticella are even free floating.  Also, this is the first time I have witnessed Seed Shrimp (Ostracoda sp.)in my aquarium.  These look something like microscopic bivalves with hair like appendages protruding to capture nutrients.  The only other major organism I could find was the occasional paramecium.
      After finishing my observations I refilled the micro-aquarium and placed it on the tray for later study.

Fig 1. (www.ucmp.berkley.edu/arthropoda/crustacea/maxillapoda/ostracoda.html)