I've bred a bunch of kribs and it's usually not too hard to get a pair established, especially when there's only 2 in the tank. I'd say that in about 3 weeks to a month you'll see a school of fry swimming around. I'm waiting to get my 75 up and cycled so I can start looking for a pair of my own again. I always had fun raising them up and now I have plenty of space to work with. There's a 75 in the living room and a 125 in the back room.