 The pH is around 8, and temperature varies little between the seasons, but ranges between about 70 and 85 °F (20 and 30 °C) between day and night.The vegetation is largely limited to algae and "Ceratophyllum" hornworts.The remnant wild population coexists with the native blackfin goodea ("Goodea atripinnis") and Lerma live-bearer ("Poeciliopsis infans"), as well as with the common molly ("Poecilia sphenops"), "Oreochromis" tilapias, and the bluegill ("Lepomis macrochirus") which presumably have all been introduced.