They are pregnant for about 27 to 29 days and are in labour for 12 to 24 hours at night
1 to 5 to 40
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Guppies are pregnant from any between 21-28 days but if conditions aren't correct, it may take longer.
Many male guppies have 'black spots' but if by "black spot" you mean "gravid spot" then no, a male guppy can not be 'gravid' because gravid is the equivalent of "pregnant" and male guppies can not get pregnant.
4-6 weeks
2 days
they should mollies arnt that aggresive but if the guppies are small enough it is possible the mollies will eat them but its not likely
When they feel they need to. :D
1 month and 2 days.
27 days
a few days a month.