The biggest on is Lightning got him and Thunder I from my LFS store in May of 18. They were the only two they had alive the rest were dead. Sadly Thunder only lasted a month before passing. Three months later was able to finally find more, Cloud and Thunder II at a LFS about 60 minutes away. Lightning was very please with his new friends. Ended up getting a 4th in late April and named him Frosty.
As for the sexing, a male's pectoral fins are longer and thicker, giving the fins a triangular shape. Females have rounder pectoral fins. Males often appear to be standing up on their pectoral fins while resting on the bottom of the tank . I would say the one with the bloodworms in the picture is a female and the other a male.
Here is a video of a very large dojo
and a couple pictures below that might be useful in sexing
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