Battery selection and charging

[mestrezat]

Need your help here. My batteries need replacing and I've got questions on how to continue. I have two 12 volt starting batteries and six 6 volt house batteries. All wet cells. I'm running a 26 year old Alder Barbour frig, radar, vhf, depth, knot, wind, auto pilot, gps, ais and a few other gadgets so I have a bit of a demand for juice.

I charge the starting batteries with a C Charger 3000 and the house with a Heart Interface Freedom model 20. Have two alternators on the engine--again one for each bank.

I need to have suggestions on the type of batteries you have on your boats and why. Wet, agm, or gel. Each has its plusses and minuses. Wet is cheaper than gels and AGMs. Gels last longer than wet and hold their charge longer. Each has it's trade offs.

My supplier has brought in Deka Seamates--8A27M and 8AGC2. I've never heard of them. I've been told by several people that Trojans were the way to go. Opinions?

Is my charging system the proper type to charge wet as well as gel? The owner's manual says yes. I've heard that AGMs require a different charging system. Yes or no?

I'm reading "The 12 Volt Bible" now to get a better education on the subject but really need everyones suggestions as to which way to go. At this stage I'm battery illiterate.