My cycle seems to be doing things it shouldn't be and I'm wondering if I should take some sort of corrective action. I started July 21st with some filter floss from a friend's tank, filled her up with tap water dosed with Prime, added enough ammonia to bring it to 5 ppm and everything went normal for a while. I experienced a pH crash on the 1st of this month and corrected that with some crushed coral in my filter which I took back out after my pH hit 8.0. What I'm worried about is my nitrites were going down like they're supposed to, then I went out of town Aug 8-11th (I asked my husband to dose the tank with ammonia every day that I was gone and he claims he did) and when I got back the nitrites had gone back up, and my nitrates went down...no water changes and my nitrates spiked at 17ppm on July 29th but went down after that and have fluctuated since. I do have some lava rock in the tank, and I've heard (although only from one source) that it can hold the anaerobic bacteria that eat nitrate but I can't figure out where it's going or why my nitrite converting bacteria suddenly stopped. I use a new API master test kit, I do shake the nitrate bottle and test as instructed, I've kept the temp at 85F for the cycle process, keep a sponge filter and AC 110 running 24/7...my daily recordings are listed below (Date, pH, Ammonia, Nitrite, Nitrate, additions & subtractions...sorry for the weird format, I keep it in an excel spreadsheet). Any advice?
8/4/2008 8.0 0.0 1.5 5.0 3ppm NH
8/5/2008 7.4 0.0 1.0 10.0 3ppm NH
8/6/2008 7.4 0.0 0.75 7.0 3ppm NH
8/7/2008 7.4 0.0 0.75 7.0 3ppm NH
Gone!
8/11/2008 8.0 0.0 1.0 7.0 3ppm NH -Coral
8/12/2008 7.8 0.0 2.0 7.0 3ppm NH
8/13/2008 7.6 0.0 3.0 5.0 3ppm NH
8/14/2008 7.6 0.0 3.0 5.0 3ppm NH
8/15/2008 7.4 0.0 3.0 5.0 3ppm NH +1 small wisteria plant
8/16/2008 7.4 0.0 3.0 5.0 3ppm NH
8/17/2008 7.4 0.0 3.0 5.0 3ppm NH
8/4/2008 8.0 0.0 1.5 5.0 3ppm NH
8/5/2008 7.4 0.0 1.0 10.0 3ppm NH
8/6/2008 7.4 0.0 0.75 7.0 3ppm NH
8/7/2008 7.4 0.0 0.75 7.0 3ppm NH
Gone!
8/11/2008 8.0 0.0 1.0 7.0 3ppm NH -Coral
8/12/2008 7.8 0.0 2.0 7.0 3ppm NH
8/13/2008 7.6 0.0 3.0 5.0 3ppm NH
8/14/2008 7.6 0.0 3.0 5.0 3ppm NH
8/15/2008 7.4 0.0 3.0 5.0 3ppm NH +1 small wisteria plant
8/16/2008 7.4 0.0 3.0 5.0 3ppm NH
8/17/2008 7.4 0.0 3.0 5.0 3ppm NH