its hard to tell with black Molly's as you cant see her gravid spot, so some signs she is that she is getting bigger, will have a more square shaped body when she is almost ready to drop, she may hang out by the heater, filter, or in some plants by herself, its hard to tell until they are about a week away from when they are ready to drop so keep your eyes open. when you feel she is ready to drop you should get a breeding net ( i find they are better than breeding boxes as some of the boxes the holes at the bottom are big enough for the babies to escape) and the net is bigger so they will have more room to swim around in, when she is done dropping take her out of the breeding net and feed her and feed the babies right away as they will all be hungry, if you dont take the mother out right away she may eat her young, she will be hungry from all the energy that just went into having her babies so make sure you feed her. hope this helps and good luck!
