Bala Shark in heat?
<Hello!  Ryan with you>
I am sure this sounds a little silly. I am pretty sure the 2 Bala sharks in the aquarium were mating. They were swimming "together" shall we say for a few moments. Then the one shark swam away faster than I have ever seen that shark swim. That was it. I guess that's pretty obvious, but I just wanted to be sure. Also I would like to know some signs that they are mating and about how long I have until I should start expecting eggs, how to care for the babies, etc.. Thank You.  
<Bala sharks are a great addition to the aquarium, where their antics are often enjoyed.  This is typical of Balas, and does not guarantee offspring.  It's like assuming you'll "breed" with every woman you've ever bought a drink!  Balas won't breed until they're at least 3-4 inches (more like a foot RMF).  Also, they're egg-scatterers.  If there are any hungry mouths in the tank, those eggs are long gone.  Your best chance for successful breeding is to separate them from the group, and feed them a high protein diet in conjunction with %25 weekly water changes.  Good luck! Ryan>

Bala Sharks 
I have somehow paired up a loving pair of Bala Sharks. They really haven't had anything to do with each other, so I thought they must be females. But today, the are swimming, rubbing and everything in between! I've read about 100 internet pages about Bala 
Sharks and 50 say they can be bred in captivity and 50 say they can't. Some said they have to be a certain age. Both are about five inches, and young, they were added to the tank about two weeks ago. I don't know what to think, they are my first set of Balas. If she will be pregnant, will you please email me with any info on the gestation and signs? 
<<Hi, I'm sorry, I have NO idea. Maybe someone else on the crew can help? -Gwen>>
>>Marina will be looking into it within the next few days.  These fish aren't "young" if they're already 5" long.  Check ya!  Marina

Amorous Bala Sharks - Marina's Reply
>I have somehow paired up a loving pair of Bala Sharks. They really haven't had anything to do with each other, so I thought they must be females. But today, they are swimming, rubbing and everything in between! I've read about 100 internet pages about Bala Sharks and 50 say they can be bred in captivity and 50 say they can't. Some said they have to be a certain age. Both are about five inches, and young, they were added to the tank about two weeks ago. I don't know what to think, they are my first set of Balas. If she will be pregnant, will you please email me with any info on the gestation and signs?
>>Ok, first, a Bala shark (a type of barb, minnow, or carp - Balantiocheilos melanopterus) that is 5" long is a "young" fish, but is at least approaching sexual maturity. If you can, take note of your water conditions, as this will be important in future. My guess is that their addition to your system two weeks ago simulated the right type of water condition changes to stimulate breeding. They are an egg laying species, which means the female can become full of eggs, but they are only fertilized externally from her body. They are considered to be endangered in their native waters. I would take the present information regarding breeding of other barbs (along with fry rearing techniques) and apply that here. As you've discovered, there isn't much published on breeding this particular fish. This means that if you keep good notations, you could add significantly to the database for this fish. Here's a place to start:
http://www.adelaideaquariums.com.au/Faqs/freshwater/fish/cyprinids2.asp 
http://fish.mongabay.com/cyprinds.htm 
Quite literally, video, photographic, as well as written documentation of breeding overtures and final behavior is helpful. Marina