So my wife works for Diventures as a swim instructor. Their main office in Fitchburg has a salt tank in the lobby and the boss told her that Big Kahuna takes care of it. I just talked with Tyler, the owner of BK. He moved out of Verona to 1010 Stewart St in Madison, vicinity, east of Fish Hatch and south of the Beltline. Web site not up and running yet but he is maintaining a Facebook page. Store is currently open by appointment only, call 608-848-1288. They apparently did some major tank upgrades, quarantine system, etc.