It will usually depend on your water temp .
Low 80's will be shorter times than mid 70's in temp.
Usually 3 1/2 to 4 weeks. Live bearers can become repeatedly pregant on even one encounter with a male. They store his "boys" somehwre in their bodies. So even when you take the male out she can be pregnent again and again.
Look for her to either be sitting on the bottom trying to be by herself, or hiding near the surface away from the male(if she can).
If she is being harrased by the male it might be less stressful to put her in the breeder. I usually dont even put a breeder in but put lots of floating or hanging gardens and plenty of bushy plants on the bottom for the fry to hide in.
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