nitrite spike after complete cycle????

Question
   fish less cycle 100% pure ammonia
 well i did my cycle for five weeks and i had a peek in ammonia of 3-5 ppm then my nitrites peeked at about 2.0 when my nitrites rose my ammonia feel so i maintained it at 3ppm until my nitrites peeked at 5.0 and then after about a week they dropped back down to zero..... then my nitrates went to about 10 -20 on the chart.... after that i feed the tank ammonia for a week and everything was working fine so i did one last test and the numbers were fine ammonia 0 nitrites o nitrates 20 after that i did a w/c and then went out to buy my fish i thought my cycle was complete....i tested the water before and after i put the fish in the tank. i only bought six small cichlids 2 pairs of each for a 75g tank b/c i wanted to see how the tank reacted with a live bio load a week later to the day my nitrites are at 1.0-2.0 i did a 40% w/c and my nitrites are still at those #'s but the fish appear to be fine eating swimming etc...
test reading 7/29/2007
ammonia 0
nitrites 1.0-2.0
nitrates 10
ph 8.2
gh 20
fh 17
temp 81
i use api Dechlorinator/Water Conditioner stress coat when i   do a water change...i changed about 75% of the water in the last three days and the nitrites just don't drop.... i was feeding the fish for the past week 3x a day maybe over feeding caused a nitrite spike and now the filter is tiring to catch up i don't know
there was a lot of food stuck in the pre filter sponges so i cleaned those yesterday and it still didn't help.. what baffles me the most is why my nitrites don't fall after a water change but my nitrates do???

75g tank.filter-wet/dry filter w/bioballs and 2 sponges one in the tray before the bio balls  and the other after the bioballs dividing the return area.

any help would be great.... thank you

Answer
Hi Rich...
I wouldn't panic. Those numbers aren't all that bad.
If you can get you hands on Bio Spira, I would use that, but don't add anything else to your water.
The only thing I would change is feed only once a day for 2 minutes. Fish do not need any more than that.
Also, keep up the water changes weekly at 75% till the nitrites level off then do weekly changes at 25%.