whens my cycle over
 

hi i have a cycling 30 gallon the nitrites are at about 8.ppm
nitrates 30ppm
ph 7.3/7.4

dont have an ammonia test yet :oops:
i have test strips so i dont know how right it is

I'd recommend getting a liquid test kit, as you'll need something more accurate for your fish. There's no way to predict when a cycle will be over, but you'll know when you have no more ammonia or nitrites.

so will they just drop or should i do water changes

Ammonia is converted to nitrites which is converted to nitrates. So everything but the nitrates will drop, and you do water changes to remove nitrates. Doing a water change generally slows down the cycle process and isn't necessary if you don't have fish in the tank. You'll eventually want to do water changes to bring the nitrates down to a safe level, but gradually, not all of a sudden. Also, make sure there's always an ammonia source being added until the fish are put in the tank.

and i am goin to change the gravel is that ok will the filter have enough beneficial bacteria