Hi Dragonlair:
If your pullets have been laying for a couple months they should be more or less out of the "peewee" egg stage, meaning their eggs are in the small - 18 oz./dzn or approx 1.5 oz./egg range. This egg weight is 'barely' sufficient to support an embryo to term and ABSOLUTELY depends on the pullet having been fed a VERY COMPLETE Breeding ration with a full complement of vitamins and minerals.
Apparently you have 8 young female birds with one male which, at first glance, is an acceptable ratio male to female, 1:8, however there are, or can be, some problems with your choice of a male Polish to mate with the other females in your flock.
"I have just hens right now, 5 Golden Comet, 2 Polish and a RIR , but will be getting more hens and a roo soon. I also have ..."
Your male Polish will likely (not necessarily) "Bond With" and expend most of his mounting time and thus his semen into the Polish females.
Your Polish pullets will likely have lots of fertile eggs after the first 3 or 4 days of being inseminated. (It takes awhile for the eggs already in the pipe to clear and they cant be fertilized once albumin deposition has begun and albumin deposition begins in the oviduct fairly soon after the ovum has dropped from the ovary. )
Your other females however may have some problems becoming fertile.
MR Polish may mount them simply because hes Male and They are Female however he may not have any juice left after dealing with the Polish females. Most of his juice will be in the cecum of the two Polish females and any he has left over for any other female especially a Rhode Island Red will simply be an accident.
Theres a lot more you need to know, however in deference to the Moderator/List Owner, Ive agreed to keep my comments reasonably benign and not bother you folks with the real total truth of chicken keeping which might upset your world view and cause you to think.
David Sullenberger,
a.k.a ProfessorChicken