i recently bought a stereo and speaker combo for the boat. Should I buy a separate battery for it or should I wire it to the switch panel, which means it would running off the cranking battery. I'm afraid it will drain the battery out on the water. Thanks in advance for any suggestions.

Probably ought to have a deep cycle battery for such doodads. If you only have a cranking battery & you run it down on the stereo you won't have a good day.

well, if your'e running amps and woofers and the whole 9, run another battery, watch the battery voltage on your GPS. Not a bad idea to keep a set of jumper cables on the boat anyhow

i run mine off of one of my trolling motor batteries.

Why not use your phone and earbuds to spare the neighbors from your taste in music?

I run my head unit and gps off the motor battery and the amp off a spare.

Definitely get a second battery. With or without the stereo issue, having the second battery is the cheapest $120 on the water insurance you'll ever have. Secondly... the amp can definitely draw down a battery. Andrews advice is sound.. at least run the amp off the second batt and remember to change the pergo switch so it will charge while running.

it's a great addition to a boat and lots of fun.
t

I run mine off my cranking battery but i also move around a lot

On behalf of everyone this^^^^

Can you run it off of the cranking battery? Yes. Everything in my boat electronically is run off of my cranking battery, 2 HDS's, head unit, amp and 4-8's, jack plate, power pole ect ect. However, I do have an over size cranking battery with excess CA and reserve capacity. I also replace and maintain this battery and TM batteries. I am able to watch the voltage level of the battery on my HDS as well as the Mercmonitor, which would both be good indicators of battery drain. If I got in a bind as a last resort, I could move over to a TM battery to get the motor started. I guess it really depends on your risk and tolerance level.