I know my platy is pregnant but can anyone tell me how much time she's got left
It depends, they say it could take about 25 days and water conditions and temp help also with how long she has left.
The belly will become flat when the birth is near. Keep an eye on it.
The drop date is totally up to the female. Female livebearing fish can hold the fry until they feel the tank conditions are right for the survival of the fry. You can encourage the female a few ways: Water changes of 50 percent of the tank's volume every few days and make the new, treated tap water a bit warmer than what's already in the tank. Add some individual stems of a fast growing, floating plant like Water sprite or Hornwort. Floating plants provide hiding places for the female and for the fry and are a good part of the fishes' diet. Start feeding a little more and a little more often. Feed a variety of low phosphate flakes, freeze dried and frozen. Well fed adult fish aren't likely to bother the fry. The combination of added food and pure, warm water with some floating plants will make the conditions just right.
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