I setup my tank a month ago with some plants and substrate and due to holiday / time I did not actually start cycling it so was just running with the heater and filter on plus the lights on for six hours (three in the morning and three in the evening). Last week I stripped the tank right down, changed from gravel to sand. I tested at this point and had Ammonia 0.25 ppm Nitrite 0 ppm Nitrate 5 ppm I then finally dosed some household ammonia (value stuff from Homebase).but went a little overboard and the test was showing up as 8ppm so I did ~35% water change and test dropped down to 4ppm. I have been monitoring all week and ammonia has stayed static at 4 ppm. This morning ammonia looked to be a somewhere between 2 and 4 ppm so I also decided to test nitrates / nitrates and I had nitrite was between 2ppm and 5ppm (hard for me to differentiate) Nitrate was 80ppm I was surprised so see high nitrates as the ammonia had not really dropped. I have done a fair bit of reading and everything points to cycling looking like (http://www.fishkeeping.co.uk/articles_51/fishless-cycling-article.htm) So I was expecting to be at the point where ammonia is starting to drop and nitrites rise but not to have any nitrates yet.... I did add some root tabs (http://tropica.com/en/plant-care/nutrition-capsules/), could these have caused nitrates to spike or is this actually the processed ammonia and the tank is cycling? I did a 30% water change again today and nitrates dropped to 20 and ammonia was down to 1ppm (nitrite remained the same). I have added some more ammonia (hopefully up to 3ppm but will test again a little later). Any explanation of what is going on?