-_-....no. kisame was said to have a high chakra amount even for akatsuki standards. no one said he had the most overall. after all he has to steal peoples chakra to beat them. nagato didnt.Well you can't argue with facts from the manga, Kisame has the most chakra in the Akatsuki higher then even Nagato
nagato killed jiraiya, took on everyone in konoha, destroyed konoha, fought naruto + frog army + kakashi + 8 tails kyuubi and confronted naruto again. still he had enough chakra to bring everyone he killed back to life.