How long does it take for a new tank to cycle

[jimipot]

How long does it take for a new tank to cycle?
I added three damsels to my tank after two weeks two of them died after a week.

 

[carrie1429]

Usually it takes 4-6 weeks to cycle. You damsels proabaly died from the ammonia and nitrate spikes. When your nitrate and Ammo. read 0 then your cycle is complete, also you will see light brown algea covering the rock and substrate witch is diatoms and a sign that your tank is through cycling.

 

[carrie1429]

Yes I meant nitrite, sorry about that.

 

[mpgt]

After cycling for three weeks my nitrites are at 0.5ppm. They're dropping real fast. I just called a big LFS, and was told that nitrites can spike several times and that it "usually takes 6 to 8 weeks to cycle a tank".
I think they'll spike once, and then again IF you over feed or stock too quickly. Am I right?