I don't really know. All I do know is that I have fish that have been in the pond about a month, some have made nice round nests and are guarding them, and there are a bunch of very young fish.

How long does it take from nest building to fish hatching?

My fish are all from 3-4" long (they've at least doubled in size) and they're starting to "round out" meaning they were slim, almost cigar shaped when I put them in and now they're more circular.

I'm pretty excited!

Now all I have to do is kill those damn blue herons! They're wiley little suckers. They have good eyes AND ears, it's hard to sneak up on them for a good shot.