Little Sletten Lake is a small, 17-acre lake with a maximum depth of 32 feet. It has very soft (unmineralized) water. Aquatic plants are sparse and grow to a depth of 6 feet. The lake bottom along the shoreline is boulder, ledgerock, gravel, and rubble. The outlet has a steep and rocky watercourse that limits upstream fish movement.
Little Sletten Lake's littoral zone (that portion of the lake that is less than 15 feet in depth, where the majority of the aquatic plants are found, is a primary area used by young fish, and provides the essential spawning habitat for most warmwater fishes) is 7 acres. The lake is approximately 32 feet at its deepest point. The lake's fish species include largemouth bass, bluegill, and white sucker.