New to Boat audio install

[califguy3535]

Someone please advise...Im putting in a second battary and amp in my boat. Question is do i run ground from the negetive terminal or somewhere else. Anything else i should know about adding the second battary.
Thanks

[Mr. Naudio]

Someone please advise...Im putting in a second battary and amp in my boat. Question is do i run ground from the negetive terminal or somewhere else. Anything else i should know about adding the second battary.
Thanks
GROUND AMP TO NEG TERMINAL
also ground from one battery to the other
use a perco and run one bat,positive to one and the other to two
pos from amp and all boat positives to common post on perco
this is if you only had one battery to begin with and can get to the perco without opening hatch.
call me if you would like 680-0203 frank