MINE DID THE SAME THING, OVER-FEEDING AND WATER PARAMETER CHANGE BOTH HAVE A HAND IN THIS, KEEP FEEDING THEM FOR A BIT UNTIL THEY ARE BACK TO WHAT IT LOOK LIKE BEFORE THEN YOU CAN CUT BACK TO MAYBE ONCE A WEEK. THAT IS IF YOU WANT THEM TO STAY THE SAME SIZE AND NOT SPLIT AGAIN.
CONGRATS, NOW YOU HAVE 2 BTA.