Water Change Question

I just want to weigh in on your opinions before I do this. My tank is a new setup- tank is cycled and had a lot of crabs,snails, a brittle starfish and a Chromis. My question is- my tank water is testing zero for everything- all of the stock seems healthy and happy- should I start the weekly water changes now or should I wait for something like an ammonia spike? I'm just afraid of I do a water change it willess something up lol.