Has my tank started cycling/will it need to??

Hi



I have just set up a 20 gallon tank with coral reef live sand and argonite, added 2 suposedly cured live rocks from my LPS.



I added some Microbelift speacial blend in to kickstart the biological cycling etc



I have been testing for ammonia and nitrates for 5 days and has read 0 constantly.



How am i to know if i have cycled or what stage im at?



btw if some of what i have said is rubbish just tell me, im completely new to this and have only leanred what i have read on forums over the last month or so...some of which contradicts others