If you want to breed them you have to be ruthless when culling. I know this sounds mean but if you dont youll end up with too many fish of low quality and never be able to give them all away.

start with the deformed and weaker looking fry then the smaller looking fry.

 As they grow older you cull the early maturing males and smaller females.

Then when they get old enough to start seeing fin development and color you cull those fish with poor fin shape and color. then you look at body size and shape and cull again.

out of 40-50 fry you should end up with a few quality males and females. then you start the process again.

beleive me I know about saving every last one of them and I really would hate to cull but if your going to be serious about raising quality fish you cull the fish that are not up to standard.

Now if you have a huge extra tank say 50-100 gallons you could throw alot of your better culls in there and then sell them off or give them away but you will have to cull some fry if your going to breed and raise guppies thats just the way it is.

Other wise you would need a lake to house all the guppies you will have within a few years ;)