Ok, I’ll look into biosecurity- my list is growing. My 2 breeders know each other through the chicken world and neither had issues with the other. I was planning to arrive early for selection, now I’m thinking it’s even more important. I’ll look into it more.
What electrolytes do u recommend? I’ll get those for sure. And as to grit, I always save my eggshells for gardening, I bake and then grind them up and save in jars, I have read about offering this. Do you agree? I have lots already. And my breeder lady suggested medicated starter feed, any other advice? I need to look into sprouted grains too…!
Calcium and insoluable grit are not the same. They won't need calcium until 16 weeks or older.
I do feed mine eggshells for additional calcium, but I also offer oyster shell. My reasoning is, if they are producing their own calcium by way of their eggshells, there will be a deficit at some point.
Insoluable grit is usually made from ground granite and helps them digest their food.
At 6 weeks, I'm not sure they need to be on a starter feed at all. A grower should be fine. You can continue the starter if you are comfortable with that and switch to grower at 12 weeks. To me it is easier to just feed everyone in the flock a grower.
You can find electrolytes at
Tractor Supply, Atwood, or just about any farm store. I don't keep a particular brand, but I always have some on hand.
You may want to read a couple of articles on emergency kits too.
Sorry, I just added to your list.

Also, be aware that 6 week Olds can occasionally be mis-sexed too. You may still get a cockrel, but your odds of getting pullets are better. Still, you should have a plan for an accidental male, if you don't want a rooster.