mixing battery types - opinions?
 

My new boat is coming with 2 cranking batteries.

In the past, I've used a cranking for the engine then a crank/deep cycle hybrid with a Blue Sea add-a-battery isolator for the electronics.

My dealer says that battery types shouldn't be mixed for marine applications - I'm concerned about not having a deep cycle for the electronics.

Opinions? Thanks.

Maybe he was referring to not mixing AGM and wet cell batteries...not starting battery vs deep cycle like you're thinking. Most of us use a "cranking" battery for starting and then one or more deep cycle wet cell or AGM batteries for stereo/lighting.

no, I specifically asked about swapping one of the cranking for a deep cycle type.

Is it ok to have one of each, provided they are of the same type (gel, wet, etc...)?

That's what we all pretty much use (especially those who run 6v batteries)...a starting specific battery and then deep cycle for accessories/stereo

I'm pretty sure you don't want different size batteries on the same bank if you are using a charger though (like having a group 27 and a group 31 on the same bank powering your stereo).