- Central Illinois Marine Aquarists (CIMA)
- Central Ohio Reef Aquarists (CORA)
- Central Wisconsin Reef Club-(CWRC)
- Chicagoland Marine Aquarium Society (CMAS)
- Cincinnati Marine Aquarium Society
- Northern Ohio Reef Keepers
- Grand Rapids Marine Aquarium Society (GRMAS)
- Greater Iowa Reef Society
- Greater Minnesota Reef Society
- Indiana - Fort Wayne Marine Aquarists Society (FWMAS)
- Northwest Indiana Marine Aquarium Club
- Indiana Marine Aquarium Society (INDMAS)
- Indiana - Tri-State Reef Club
- Joliet Area Reef Club
- Kansas City Reef Association
- Mahoning Youngstown Saltwater Enthusiast Association (MY-SEA)
- Marine Aquarium Society of Illinois Valley (MASIV)
- Marine Aquarium Society of Michigan (MASM)
- Mid-Missouri Saltwater Aquarium Club
- Muskingum Valley Reef Club
- Nebraska Reef Club
- Nebraska Marine Society
- Northern Illinois Reef Club
- Northern Indiana Marine Aquarium Society (NIMAS)
- Northern Wisconsin Reef Society
- Northwest Ohio Reef Association (NORA)
- Red River Valley Aquarium Club
- Rockford Reefers
- Saint Louis Area Saltwater Hobbyists (SLASH)
- Saltwater Enthusiasts Association of Springfield
- Saltwater Enthusiasts Association of St. Louis (SEASL)
- Springfield-Decatur, Illinois Reef Builders (SDIRB)
- Springfield Illinois Saltwater and Reef Fanatics
- Upper Peninsula of Michigan Marine Aquarium Society
- Wisconsin - Fox Valley Reefers Club (FVRC)
- Wisconsin Reef Society (WRS)