What level of ammonia were you dosing it to? I did mine at around 4ppm and with the water from my tap it took right at 5 weeks to fully cycle. But when it was done it was so ready. No issues whatsoever. I'm ready to see some skrimps. I've had a number of Nerites and like a lot of aquatic life you never know how long they'll live. Some have lasted quite a long time, well over a year. And others have done well for months but then suddenly died off. I think with the Nerites all being wild caught you really don't know where they are in their life cycle if they're of a mature size when you get them, other than they're adults.
I'm looking at moving in the next few months, I've been here for 7 years now, and I'm already starting to plan and dread. Mostly dread. I may take it as an opportunity to completely downsize to just the 55. I consolidated 6 tanks into 2 and still find that a bit much on busy weekends. We'll see. I have plenty of filtration and everything is compatible so not really too concerned about overstocking or aggression issues but it will definitely be a full house if I go that route.