Oh dear. Are two of my Balloon Mollies pregnant?

[Platyface]

We have three Balloon Mollies in our fish tank. Two of them, lately, have huge bellies, one of them bigger than the other. I know i'm not overfeeding them because none of my other fish are like that, and the third Molly does not have a huge belly. So, we figured that two of them are pregnant. We reasearched Balloon Mollies and found out that they are livebearers, have a 50-60 day gestation period and can have up to 32 babies at once. So, if they both get to the maximum, 32 babies, I'll have 64 new balloon mollies. And I only have a 57 l aquarium. I think we'll have to get another tank, since this one is slightly overcrowded anyways, and give some of the new generation of mollies away to friends who have tanks.

My mom is slightly terrified at the thought of possibly getting 64 baby Balloon Mollies.

[bscman]

It's worth noting, though, that it's not likely all of them will survive, or that you will get a full 64, or that your adult mollies don't eat many of the young.

I'm not a molly breeder, but I see a 50-60% survival rate for guppies (also live-bearers) when I left them in the tank with adults....severely LESS survive if there are not a LOT of plants and places for the young to hide.

[Cichlidsrule]

There's a thing called the gravid spot that turns black when a female molly is pregnant. It's located near the anal fin. Of course, if you have black mollies, this doesn't help....
If they do wind up giving birth, keep them in with the mollies and the other fish. The babies will most likely be eaten.
Could you post some pics of your mollies? That way we could identify whether they're pregnant and which ones are males and which ones are females.
Here's a pic of a black male molly:

The arrow is pointing to the gonopodium. This identifies the molly as a male. Those of your mollies that have those are males and could potentially impregnate your females again.

[oliesminis]

by the way. they can also give birth to many more than 32. ive heard of births over 50

[swordtailbreedr]

yeah. easy.

[ronnfive]

Hi, first of all mollies are almost always pregnant… the full size of the balloon molly is about 2-2.5 inches, seldom 3”. The usual gestation period of this fish is about 30-32 days. About the number of babies, it does really depend on how big your molly is. I got a really huge 2.75 inches balloon molly, diameter of about 1.75 inch, and got over a hundred of live fry, unfortunately, she got a lot of loads of unfertiled eggs too (probably, due to the transfer from LFS to my tank). Like what you’ve said, you got a crowded tank, thus the reason why she’s not comfortable to drop her fry. --I find this useful when she’s about to drop… (I can tell when she’s ready because of her boxy shape) …I moved the other fishes to my other tanks and leave her alone. Put plants in her tank (specially floating plants) and get ready for the upcoming babies. The more plants the more chance of fry survival. Feed her live food once a day (daphnia is the best coz the babies will eat them too). Change 5-10% of water daily. This works for me, but I would recommend it if your other tank has almost the same water temp so that your other fish is not too much stressed! hope this has helped!

-ronn