I installed about 200 into a 1/4acre nursery pond that didn't have any other fish in it. The shrimp were all filled with eggs when I installed them about a month ago. I haven't seen a lot of activity but the pond went from light clear green to a muddy water. . I'm pretty sure it's from the shrimp but can't 100% confirm. I'll try the flashlight trick. Anybody know how fast they grow? I plan on seining in June or July to see what's going on.