I'm a bit unsure as to what is happening with my tank/filter. I didn't have much luck using Sulphate of Ammonia. I dosed it up to around 5ppm of Ammonia, and the tank just sort of sat there for 10 days, not dropping, not getting any Nitrites/Nitrates. So on the 5th of March did a 50% water change getting the ammonia down to around 2.5ppm. And again for 4 days nothing really changed, slowly dropped to around 2ppm. On the night of 9th did another large water change, getting the Ammonia down to 0.35ppm. This was the last night I had before leaving on my holiday for 2 weeks. Added a large pinch of fish flakes, and setup an automatic feeder to drop in small amount flakes once a day while I was away. I tested the water once more before I left for the airport on the afternoon of the 10th. And I had some Nitrites, so I left on my holiday feeling happy that my tank was on the way to being cycled. Got back home on the 24th March. The Auto feeder had filled with condensation and had gone moldy/gummed up. So no idea how long it managed to feed the tank for. Tested the water, had about 0.5ppm ammonia, 0 nitrite, and 5ish ppm Nitrate. Did a 35L water change, removed a plant that had died (maybe I should of left the lights on). And put in some more fish flakes. Hoping to get a bit of a ammonia spike, nitrite spike, and increase in nitrates. After 3 days (each day adding a pinch of flakes), basically saw no change, 0.5ppm ammonia, 0 nitrite, maybe slightly higher nitrate levels. On the 27th & 28th gave really quite large pinches of fishflakes. 29th finally saw Nitrites creep above 0. At this point, there is a lot of moldy fishflakes at the bottom of the tank, on the plants/ornaments etc. So did a 40L ish water change, vacuuming up a lot of the detritus. This was done on the thought that the tank is now pretty loaded up with a lot of rotting crap. If I remove the majority of it, I should hopefully see the water getting down to 0 ammonia pretty quickly. Checked the levels on the 30th, 0.5ppm ammonia, 0 nitrites, 5-10ppm Nitrate. Checked the water again this morning (31st) and levels are up to 1ppm ammonia, 0 nitrites, 5-10ppm Nitrate (closer to 10). Even after my vacuum up of moldy fishflakes, there is still quite a few left, some probably getting dragged up the filter too with all the water getting stirred up. But there is a lot less of it then before, so I would of expected the load to be lower. But perhaps with some of it getting in the filter, it is exposed to more air so perhaps is rotting more quickly? Should I just leave the tank at this point, and let the last of the detritus decompose? Would it be worth me getting some used filter media from someone here to make sure my filter is well seeded, and do another round of cycling? I'm excited to put some fish in, but not until the filter/tank is ready. And a bit confused as to why it is not quite working as expected (i.e. after a clean up the crap, ammonia levels increasing a bit, rather than dropping). Thoughts, recommendation, help?