I have a breeding pair of Betta rutilans who live together in a 10 or so gallon tank and spawn like clockwork every second week or so. My male usually holds the eggs in his mouth for two or three days and then makes a bubble nest and puts the hatched fry in.
I have one juvenile in there that I found a month or so after it was born. This fry was born after my male brooded for about a week so it was larger than most betta fry when it came out. Since this complex of betta doesnít eat its own fry, Iíve just been leaving whatever is hatched in with the parents to grow (this is recommended).
Over the past month around 15-20 fry have been hatched out. However, I havenít seen any of these fry once the male stops tending the nest. So is my juvenile eating the other fry, or could they just be hiding like my juvenile did for the first month or so of its life.
Iím half tempted to raise this batch separately, but I donít have any food for fry and theyíre so young Iím worried about any sudden changes killing them off. So does cannibalism exist amongst betta fry? Iím assuming it must, being competition and all that. I think Iím going to make a separate grow-out tank and order some supplies online so next time I can actually monitor them.