This protozoa is called Actinophaerium (Patterson 169). I observed at least two of them in my aquarium.
This is a sampling of the other types of protozoa I found swimming around the empire. This one here, a species of Paramecium (Patterson 153), is swimming amongst the filaments of the new algae growth.
I also found a very matured cyclops (Covich and Thorp 789) darting around in the algae. It reminds me of a shrimp-like creature. The two nodes attached to the bottom of the cyclops are pouches containing developing larvae. After desperately trying to track this little guy down, I managed to capture this picture.
I also managed to find and identify the subsequent form of this larvae called nauplii (Covich and Thorp 789). I am certain that there are more than one of these guys in the aquarium, but they are so fast I only saw/took a picture of this one. I found Randall once again, but she was not difficult to spot at all. She has grown so big! Hanging out in the algae again, I don't think she ever stops eating. This is just a head shot, but it appears hat she has grown in length by at least 25%.
In addition to these new creatures, I observed a noticeable growth in number of nematodes within the aquarium.
References for Identification:
Covich, Allan and James Thorp. Ecology and Classification of North American Freshwater Invertebrates. San Diego: Academic Press, 1991. 789.
Patterson, D.J. Free Living Freshwater Protozoa. Washington, D.C.: Manson Publishing Ltd., 1996. 153, 169.