Zero morph questions
 

Do they usually darken with age? I don't se many het for zero's. Is this a morph that can make hets?

The zero morph is a receive trait and you can make hets when you bread a zero to another dragon. I have noticed as they get older they can look brighter or more silver in color just depends on the dragon, Hypo zores are almost bright white its pretty cool. I hope this answers your questions.

Yes the recessive trait can produce hets. If you breed a zero with another dragon you will get het for Zero.
They tend to be dark when they shed.
I'll agree the whiter the prettier. Striving for that truly white dragon.