SJE Inc.

SJE has been leading the water & wastewater industry since 1975. Founded by Steve Johnston in Detroit Lakes, MN, we now have 7 locations worldwide and have customers in every continent except Antarctica. We are known for our innovation, high-quality products, and exceptional customer service. We own three brands—CSI Controls, Primex, SJE Rhombus—each of which is known for its high-quality products. We’re committed to creating innovative solutions that help municipalities, industrial customers, and homeowners meet their liquid level control needs. We also offer custom PCB solutions through our SJE Rhombus brand, including circuit board design, embedded controls and software, and more. Our headquarters is still in Detroit Lakes, MN, just down the road from the house where Steve Johnston started it all over 40 years ago.