The Race for World Dominance

Only two weeks into the experiment, and the growth is astounding. I imagine this is owed mostly to the decomposing food matter I identified that had been introduced to the MicroAquarium. I extracted the details from the class blog: "Atison's Betta Food" added October 21 made by Ocean Nutrition, Aqua Pet Americas, 3528 West 500 South, Salt Lake City, UT 84104. Ingredients: Fish meal, wheat flower, soy meal, krill meal, minerals, vitamins and preservatives. Analysis: Crude Protein 36%; Crude fat 4.5%; Crude Fiber 3.5%; Moisture 8% and Ash 15%. Where previously locating an organism to view required a few seconds of probing, now tens of organisms were competing for food and space in any given section. Almost all of the organisms were many times smaller than a millimeter and much more diverse. Some of the same organisms were present. A few I had not identified before such as Uroglenopsis (Pennak 1953 p. 41 Fig. G), Enteroplea lacustris (Pennak 1953 p. 200 Fig. E), Paramecium (Pennak 1953 p. 25 Fig. E) were still thriving. I was able to even identify the large green sacs that I had noticed unmoving and scattered around the aquarium last time as rotifer eggs (Pennak 1953 p. 174 Fig. A). In addition, the number of diatoms had significantly multiplied, but the varieties were relatively the same. A common one looked very similar to the rice-shaped one from last week, but with a budding protuberance on each narrow end.

 Actinosphaerium

The first new organism I discovered feeding near the now deceased carnivorous plant was Euplotes (Pennak 1953 p. 69 Fig. B). While I was observing him he swam right into the most interesting looking spherical organism with long flagella, Actinosphaerium (Pennak 1953 p. 57 Fig. C). A plethora of organisms were gathered in the area encompassing the added food. One such organism was Holosticha algivora (Bick 1972 p. 19 Fig. 8C), drifting on the outskirts. Others I observed gathered near the feeding frenzy were  Stylonychia mytilus  (Bick 1972 p 174-175 Fig 88) and Thuricola (Pennak 1953 p. 72 Fig. H). There were also many more rotifer eggs dispersed throughout this trafficked section at the top of the MicroAquarium.


Pennak RW. 1953. Fresh-water Invertebrates of the United States. New York. The Ronald Press Company. 25-200 p.
Bick H. 1972. Cilated Protozoa. Geneva, Switzerland. World Health Organization. 19-175 p.