I dont think you need to take the tank apart, just keep an eye out for more nymphs. When I set my 10 gallon up, I had a couple of them. Don't think they ever took a shrimp out as they were tiny and all the shrimp were adults. But, I just made sure to really scan the tank multiple times a day and when I saw one, out he went.
There's only a finite amount of nymphs in the tank, they aren't going to reproduce.