I used a CAPAC system but it is a PITA. I wondered why the previous owner had disconnected it so I tried it for a year and abandoned it too.
Firstly it uses 12 volt power so unless you are a cocktail boat, keeping batteries
up becomes a problem. Second, it concentrates the protection at a limited number of electrodes that attempt to cover the whole hull
. With enough voltage to get the correct level of protection as measured by the control cell location, the areas around the electrodes becomes over protected. The DC current in this area causes ELECTROLYSIS
in the seawater forming Chlorine gas bubbles which will eat the antifouling paint
off the adjacent hull and bleach color out in streaks rising to the surface.