Blue Algae Boil is a 5th magnitude spring with a spring pool approximately 15 feet long by 10 feet wide. The vents are not easily recognized due to the large amounts of organic material, blue-green algae, and sulfur-reducing bacteria. The spring flows toward the southeast for about 75 feet to the Sulphur Run of Black Water Creek.
Blue Algae Boil is located in the Seminole State Forest about 1.8 miles southeast of Cassia. From the south entrance of Seminole State Forest on State Road 46 (about 0.4 mile west of the Wekiva River), turn north and drive past the stop sign, through the gate, and cross the bridge over Black Water Creek. Drive about 0.2 mile from the bridge to the next intersection, then turn right and go another 1.1 miles. Park and walk toward the northeast about 175 feet down the slope and out into the floodplain to Blue Algae Boil (depending on where parked). Access and fee information can be obtained at the Seminole State Forest south entrance.