we just started our tank 3 weeks ago. we have 4 damsels in a 70 gal tank, and about three days ago I noticed that one of the blue ones is super light in color copmared to the other one. I tested the nitrite levels and they are super high. My husband did a partial water change, and I retested the water last night, nothing has changed. The fish still looks pale, no white spots, he is still active and eating though. I don't know what else to do. We are newcomers at this too, so that doesn't help much. Traditionally, how long does it take to cycle? Any more suggestions? Thanks.