Any difference in color,size between M/F?
In most kingsnakes, males get larger than females. I believe this is true in pyros as well, although I don't recall ever hearing this stated for sure.
Would a 30 gallon long tank be sufficient?
If it is a 30 long (36" long), it should be fine.
Temps hot side-cool side?
My pyro rarely gets on the hot end of his cage. I have heat tape there that gets it up into the mid 80s. The cool end is in the mid to low 70s and he stays down there except right after eating.
I would say a cool area near 70° and a warm area around 85° would be optimal.
Are they happy on mice or like grey banded prefer lizards if given the choice?
I collected mine from the wild as a juvenile but it has always taken pinkie/fuzzy mice. Some neonates can be picky and I have heard that wild caught adults can be a little picky, but most cb animals I have dealt with readily ate of the appropriate size.
Do they do best with a winter cooling period(wont be bred just a pet)?
Mine goes off food every winter, so I cool him down. I don't have a female so I don't intend to breed him, but I do cool him anyway.
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Chris Harrison