Pregnancy

Question
I have a Mickey Mouse fish, she is quite fat. How can you tell if she is pregnant or just plain fat? If she is pregnant what do I do? Thank you!

Answer
Hi Tanya;

If she seems to act normal otherwise, she probably has babies growing in there! How cool is that?! Even cooler, platies are livebearers so she will release live babies. There are eggs in her right now so once the babies are mature enough inside the eggs, they hatch inside and she will release them.   

When platies and other live bearing fish are ready to release their babies they will hide more and will develop a "boxy" look to the belly. The belly will flatten out a bit on the bottom and sides when delivery is about 5 days away.

A separate tank is best to use for her to have them in and then remove her once the babies are all released. It can take several hours. She will eat the babies, and so will her tankmates so they are safer if in their own tank. Any tank of 10 gallons or so with a heater and gently air operated sponge filter or other slow running filter will do. Babies can get sucked up into some other types of filters. Change 25% of their water twice a week and they will grow fast so you can move them to the main tank. Once they are about 3 times the original size, or too big to be eaten by the other fish they can move with the others.

If you don't have a baby tank to move her to, provide plenty of hiding places for the babies and leave her where she is. Some may get eaten but hopefully there will be some smart and fast little guys in there that will survive. Densely planted live plants are the best because they have tiny soft places to hide and microorganisms on them for the babies to feed on. Anacharis and java moss are the best ones I have used. Babies are usually born just before dawn so look in there in the morning when the sun is coming up. The babies won't eat for the first several hours so don't worry about it until the next morning. Feed them finely crushed flake food 3 to 5 times a day. Only a tiny bit though. Here are some web pages to learn more and how to care for the babies, which are also called "fry";

http://www.atchison.com/fishinformation/breedinglivebearers.htm#Fry
http://www.bellaonline.com/articles/art8344.asp
http://www.fishforever.co.uk/livebearers.html
http://badmanstropicalfish.com/profiles/profile4.html
http://www.liveaquaria.com/product/prod_Display.cfm?pCatId=1068

Have fun!

At Your Service;
Chris Robbins