I have read in numerous publications that a pH any lower that 6.0 will dramatically slow the nitrification process, as dropping the pH to 5.0 or below will inhibit the bacteria from growing completely. 8.0 is what I thought to be ideal for the bacteria.
The first time I added ammonia to my system I added WAY too much, bring the pH to over 8.8! I had to do a complete water change, and after that I was reading 1-2ppm ammonia and 7.5pH without adding more ammonia after the water change. This is what started to worry me in the first place, just the thought of adding way too much may mess it up. Every day since I have added a small amount of ammonia keeping the ammonia levels around .5. Three days after doing the complete water change and adding drops of ammonia daily, my nitrites went to .25ppm, the next day they were still at .25ppm but i was also reading 1ppm of nitrate. The next day, ammonia was kept the same and nitrites still reading .25ppm but the nitrates went up to maybe even 4ppm. The pH dropped all the way to 6.0 almost overnight, i did a 40% water change bringing the pH back to 6.4 which is what its currently at. But I am reading even less nitrites and nitrates now, seems to me the sudden pH drop stalled the cycling possibly.
I did not use anything besides ammonia to help with the nitrification process. My 2ftx4ft grow bed is full of hydroton (expanded clay pellets) so I have a HUGE amount of surface area for the bacteria to grow on. It constantly floods and drains giving it good oxygen circulation. I set the temp. to 85 but I know that warmer water doesnt hold oxygen as easily, so I need an airstone. I was very surprised when I saw my nitrate test had turned light orange (1ppm)
