Do you have any livestock or just live rock? If just LR I think it may be best to not do water changes as you want to get your population of nitrifying bacteria going (I have heard of people actually dosing with ammonia to speed up their cycle...not sure if I would try that myself). If you have livestock then I would start water changes to keep ammonia levels below dangerous levels (which depends on what you have)
Just my newbie opinion
Francis