Can't say I've heard of a spotted bullhead before. Yeah I've breed Yellow Bullheads in my pond outside. No I don't know how to sex them. I just got lucky! Like I said in a previous post, I caught 3 of them when they were about 2 inches long and I stuck them in my turtle pond. That was about 4 years ago and they're both about a foot long and breed under a large rock in the middle of my pond.
OK, lol alot of people always say that they never herd of a spotted bullhead, or like the petstore I got it at, the old guy laughed in my face and said there is no such thing. sooo, I finally caught them and got a picture of them for anyone who wants to see, lol. hopefully I have myself a boy and a girl, b/c I love these little guys, they never leave each others side.
They are very pretty.You should have a flower pot or large pipe in their tank/pond for them to breed in. Good luck with breeding them. When it warms up I'll have to take a picture of my Yellows.