Paramecium is a genus of unicellular ciliated protozoa, commonly studied as a representative of the ciliate group. Paramecia are widespread in freshwater, brackish and marine environments, and are often very abundant in stagnant basins and ponds. Species of Paramecium range in size from 50 to 330 micrometers (0.0020 to 0.0130 in) in length. Cells are typically ovoid, elongate, foot- or cigar-shaped. Paramecia feed on microorganisms like bacteria, algae, and yeasts. The first kind of food young fry of the smallest fish species need is Paramecium. Please download the Paramecium Culture Manual listed here.