I'm looking for opinions on how many rats I should keep in each tub in my racks?

Two scenarios:
1) Male with females for breeding.
2) Females with their litters.
(Females give birth and stay alone in lab cages for 7-10 days before moving)

Two tub sizes:
A) Petco Jumbo litter pan - 22.25" X 16.75".
B) Lowes small mixing tub - 26" x 20".

Here's what I was thinking. Should I go higher or lower on the number?

1A: 1 male & 4 females
1B: 1 male & 6 females
2A: 3 females & litters
2B: 4 females & litters

Thanks.