As gaby said, you aren't going to 'lose' a cycle, the bacteria will adjust to the bioload. I'm not sure why everyone thinks that a tank will un-cycle if it doesn't have a big ammonia source, I can only speculate that it may be because of the ppm
#'s thrown around during a fishless cycle. Either way, it'll be fine, just let it get established, the more stable the parameters the better.
When I first started my shrimp tank(s) I tossed shrimp in with plants, and they did o.k
., but others did not. It was pretty hit and miss, but I did notice after a few months the tanks all did well, so take it for what it's worth.