cycle question

[gmann]

I started end of Dec. using dry rock, i ghost fed fish food for a couple days until i got ammonia, and dumped a bunch of zeo start and zeo bak on day one.

On day 5 i started dosing every day based on tank size.

ammonia came n left
nitrite - came and left without me even knowing
nitrate was at 25ppm and is recently shot up to at least 100ppm.

at this point is my cycle over? do nitrates go down on their own, or will i need to do a series of water changes?

thanks