Need some help with fishless cycling

[tylixxa]

My tank has been processing 2.5-5ppm of ammonia for the past two weeks and nitrites have remained around 0-.5ppm. Nitrates though never got over 10ppm............... UNTILLLLLLLLLLLL..............
today! Did a 80-90% water change and added fresh water to the tank. Thinking that by tomorrow I will be able to add some fish since the fishless cycle is finally over (thank God), this has thrown me for a loop. The ammonia reads .5ppm, which is good. pH is about 6.8, good too. Now this doesn't make sense... nitrIte is 5ppm, and nitrAtes are about 15ppm. Now how is that possible? I dechlorinated the water after I put it in the tank, and it has been running for about 5 hours now. I have yet to read anywhere that this has happened to anyone, and I don't know how nitrite and nitrate have risen by adding fresh water and dechlorinator. Can someone help me??
By the way, this is a 37 gallon, and I'm doing a FISHLESS cycle.

 

[luxum]

It sounds perfectly normal to me. Just it wasn't nearly done as you thought, rather it was about to enter the second phase, the high nitrite phase. Usually takes a bit longer than the ammonia to drop. Then your nitrates will be really high and you'll need to do some water changing before adding fish. Don't do any more water changes right now, let the nitrite build and wait for the colony to catch up to it.

 

[tstenback]

i Agree with luxum. Your tank is still cycling so be patient it looks as if everything is going fine. It is just going to take time.