Ok. So I could use a little help here. I have been doing a fishless cycle on my 29gal tank for about 6 weeks. I had my ammonia spike and then my nitrite spike. I tested my water tonight and had 0 ammonia and 0 nitrites. I did a water change and cleaned the gravel with a vacuum. I scrubbed some of the decor with a toothbrush to help get rid of the algae but now my nitrites are back up to .50ppm. What happened? Did I get rid of some of the bacteria?