I am looking to replace my current flooded batteries and am interested to hear opinions on gel vs AGM.
I will be looking at 3 x 120 Ah.
Also interested to hear peoples thoughts on No of batteries, should I be looking at 3 x 120 or 2 x 180

Likewise, I've been very happy with my AGM batteries. I went with 100AH batteries made by Ultimate . They are so-called "dual purpose" deep-cycle batteries which means they can supply enough cranking amps to serve as starter batteries, but also tolerate deep cycles to serve as house batteries. This means that all my batteries on board are exactly the same type, which in my case is the following:

4 x house battery
1 x starter battery
1 x VHR radio battery (required for survey)
1 x Hookah dive battery for electric compressor

If I'm unlucky enough to have a dead starter battery and a dead house battery bank, I still have two spares

Thanks for your input guys.
I have based on 12 amp for 10 hours to support auto pilot , nav lights , fridge and auxiliaries. Giving a total between charge of 120 amp hours.
I have just purchased 3 x 120 ah Ritar agm batteries and will look at a 4th when budget permits.

I swapped out my flooded regular batteries about 18 months ago.
I had 2 x 165ah fitted and they lasted around 3 years before needing to be replaced.
I swapped to 2 x 210ah batteries AGM (ROLLS) and they are excellent.

they charge so much more efficiently from a wind turbine and solar panels.
I live onboard all year round and in the summer when I don't need heating I rarely need to plug into mains power.
The additional amp hours have sufficiently reduced resistance which mean the wind turbine is that little bit more efficient at charging the batteries.
I can run the fridge and all nav equipment it its windy enough.
it was a squeeze to fit the bigger batteries in but worth every penny.

sirgallivant said..
Biiiiiiiiiig advantage of agm's - beside other features - that one can fit them sideways or even upside down if needed!

Caterpillar list them so Ill harass spare parts at work today
caterpillar.scene7.com/is/content/Caterpillar/C338971

Looking good on this part number
parts.cat.com/en/catcorp/uninterruptible-power-supply/250-0477

Ill sort out the specs at work on Wednesday and see what else is around