Deep cycle?

[spareparts]

if its got a computer on the engine, the manufacture its most likely requiring at least 850 CCA. Mercury requires more on their Verado's. Unfortunately, the only thing available to meet Mercs spec that will fit in the box is AGM batteries, I throw those POS in the pile all the time, especially the optimas. 30 years working on boats, very hard to beat a Deka 24M7 starting battery. BTW, you cant mix AGM batteries and wet cell if they are charged by the same source.