Here's a list of CALI aquarium societies:
California
Bay Area Reefers (Hayward)
California Betta Society
California's Organization of Aquatic Show Tropicals (Costa Mesa)
Camellia Koi Club (Sacramento)
Central Valley Reefers
High Desert Koi Fanciers (Palmdale)
Inland Koi Society (Riverside)
Koi Club of San Diego
Marine Aquarists Roundtable of Sacramento
Northern Valley Reefers (San Joaquin County)
Pacific Coast Cichlid Association (San Jose)
Pan Pacific Guppy Association (Riverside)
Sacramento Aquarium Society
San Diego Killifish Group
San Diego Marine Aquarium Society
San Diego Tropical Fish Society
San Francisco Aquarium Society
San Francisco Bay Area Aquatic Plant Society
Southern California Killi Club
Southern California Marine Aquarium Society (Santa Ana, Orange County)
Here's the link to the listing site with links to individual society sites:
http://www.aquaworldaquarium.com/Local_Fish_Clubs.htm