batteries, one or two?

Hey guys, in the process of my first pontoon project boat. Im preparing to start roughing in the wiring while i have the deck off. Had a few questions before i purchase materials. should i use marine grade wire? should i run wires in any type of plastic/flexible conduit? I did purchase some liquid electrical tape to protect connections but im thinking twice about that, is it necessary or one of those things you wish you wouldnt have done later on? Im also trying to research battery options. cant decide between dual purpose or using two batteries (one for start/one for accessories). My pontoon has a 1980 100hp 2 stroke chrysler motor and not sure about the CCA or CA needed as well as AH needed. im planning on having 4 micro led lights, stern light (not led), 2 dock lights, pair of red/green lights, horn, dash lights and stereo. I know theres alot of questions here but help with any of them would be greatly appreciated

Re: batteries, one or two?

Dup

Re: batteries, one or two?

Battery choices most of the time comes down to personal choice.
Most of the stuff you have listed can run off any type battery.
Only Question I have is how many watts is the stereo?

Battery life is more about how you care for your batteries than the type. Lead acid batteries need to be kept fully charged for long life. If you discharge during the day they need to be fully recharged as soon as possible. The longer discharged the shorter the life.

Starting Batteries can only be discharged about 20 percent without damage.
Deep Cycle can be discharged 50 percent without damage.
Still both need to be fully recharged as soon as you can.

If the batteries are going up front in a light boat where they will be subjected to lots of pounding then marine batteries hold up better.
If they are going in the stern then I think Auto batteries work just fine.

I have got all my batteries from Costco except for my Delco Deep cycle that I got from Price Club before they changed to Costco.

Auto batteries have a 3 year free replacement and 100 month pro rated replacement.
Deep Cycles are Only 1 to 3 years Max.
None of my batteries have ever failed in under 6 years, but I recharge both batteries on board with a 65 amp alternator and when I get home the charger is put on as soon as I get the boat backed into it?s spot. Then we unload the boat and clean the fish.
Then cover the boat and check the charger. In my case it will always be fully charged by this time so I disconnect the charger that also charges thru the same battery isolator as the alternator.

Since batteries self discharge and they discharge faster in hot temperatures I charge one time a month in Summer and every other month in winter weather the boat is used or not.

If you have a Large Hi Amp Stereo or a Electric Trolling motor then a Deep Cycle holds up better.

One thing that I also have done is buy the same size battery that fits my truck that I tow the boat with. It just give you one more option if one battery dies or is stolen you can still get home with a simple battery swap.

I use the liquid electrical tape for wire connections that will be under water for launches but for the rest I just use heat shrink.

Re: batteries, one or two?

I doubt anyone will tell you that having 2 batteries is stupid, can never be too careful. For your purpose I vote for a single, large, dual purpose battery since you're running led lights and they draw next to nothing. I ran one on my 22 Cruisers for a few years before upgrading to dual batt's and had zero issues- and a great lakes trolling vessel will absolutely DESTROY batteries in short order with constant drain of high powered electronics and old style incandescent lights. I would run the wires thru conduit so it can be accessed somewhat easily if need be, and on any open boat like a pontoon or skiff- ALWAYS USE MARINE GRADE WIRING! Since you didn't mention a trolling motor, you can leave out the deep cycle batt's if you want.....this is where a dual purpose marine batt fits best.

Re: batteries, one or two?

Thanks championship and boatist. Seems how my stereo is not a high wattage set up as well as the fact that i wont b using a trolling motor, I will go with the duel purpose and oversize it a little. I can always add the second battery if i decide to install more accessories later on. I feel better with this now thanks to your advise, very much appreciated!