Hey Guys,
  I'd appreciate some input from you who are more knowledgeable than I when it comes to boat batteries. I need to replace mine. I have an 85 horse outboard, running lights, fish finder and bilge pump that run off one 12V battery. I'm wondering if I need or should have a marine battery, or if a regular car type would be good enough? There is a charging circuit in the motor so it will keep it charged unless I'm using my gas trolling motor. I have a deep cycle battery for those times I'm using my electric trolling motor.
                                  Thanks in advance,

I would spend the extra money on an optima marine battery. A regular car battery will work but the optima will last longer and is designed to resist vibration from running on the water

Thanks Hoss. You echoed what one of my co-workers said. I'll definitely consider it!

Interstate Marine batteries are reliable also. Two suggestions when it comes to batteries... Group size and CCA. If battery weight isn't an issue, get the biggest group size that will fit in your battery tray/box and in that group size, get the biggest CCA available. This will allow for the most run time.

Do not confuse Cold Cranking Amps with battery capacity. CCA is the amount of amperage available at 0* F to start an engine. Not a lot of relevance to fishing boats there! When purchasing a starting battery, look at Cranking Amps which are measured at a higher temp. For a trolling motor battery look at reserve capacity or if available Ampere Hours (AH). A marine battery is always the best choice for a boat due to a number of design features with vibration resistance high on the list. Marine batteries are also vented differently to help reduce water entry into the battery.

Wal-Mart Everstart Maxx Marine. I have 2 of these on my boat , one is a dedicated starting battery, the other runns all accessories. Had them for 4 years now and never a problem. About $80 each.

Tom, you are correct - that's what I meant to say. Thanks for clarifying.

After almost 40 years as an auto mechanic, I have learned a bit about batteries!