About 3 years.

Not sure why they would stop growing.

I do know though that when koi spawn, they eat the eggs and the fry are not recognized as 'fish' until the fry are about 3 days old. Spawining typically will occur quite early in the morning - I have seen mine spawn while I am getting myself together for work, but I am leaving my house by 6:25 am.

Mine typically spawn July/August - yours would be earlier than mine.

Do you have bullfrogs in your pond? Truth be told, I put the bullfrog tads in every spring to take care of the fry. They became too much, every fall, trying to find homes for all the fry. I do have a lot of places for them to hide in my pond though.

Oh yes, have frogs, toads, minnows, turtles, blue herons, snakes, and now even an alligator in the fishpond. I have always heard that fish will only grow to a size maintainable in the size aquarium you have. I think these koi are as big as they are going to get in this pond, AND with me not feeding them.

TK

That is true of goldfish. I have heard that of koi and I have also heard that koi will grow to the size they are genetically progammed to grow. The information tends to be all over the place.