I've been measuring the params of the water in my tank for the last 4 days. I know this isn't long, but the tank should have already been mostly cycled, since the tank was set up as a coldwater tank before. However, I stupidly changed the filter medium, and then had to change the substrate as it was causing the PH to rise very high, so I believe the tank is going through a mini cycle. I've been testing every day, usually more than once, and the params have been like this: 5th July AM
Ammonia 0.25, Nitrite 0, Nitrate 0, PH 8.4 PM
30% water change carried out, substrate removed. 6th July AM
Ammonia 0, Nitrite 0, Nitrate 20, PH 8.0 PM
30% water change carried out, new substrate added, plants added. 7th July AM
Ammonia 1.0, Nitrite 0, Nitrate 10, PH 7.4
Two pieces planted bog wood and two apple snails added Following 30% water change Midday
Ammonia 0.25, Nitrite 0.25, Nitrate 10, PH 7.4 Following further 30% water change PM
Ammonia 0, Nitrite 0.50, Nitrate 10, PH 7.4 8th July AM
Ammonia 0.25, Nitrite 0.50, Nitrate 10, PH 7.4 No water change carried out, on advice to keep things stable PM
Ammonia 0.25, Nitrite 1.0, Nitrate 10, PH 7.4 30% water change carried out 9th July AM
Ammonia 0.25, Nitrite 1.0, Nitrate 10, PH 7.4 30% water change carried out
Tank is 35 litre, and had something that's been ID's as a CAE (yes, I know it needs rehoming, I'm on it) in it when it was coldwater, which is still there, and the two apple snails I added. Filter has been squeezed in a bucket of tank water because it got clogged with plant bits and was not being effective.
I want to know whether these results are normal for cycling. So far, everything I've read about the nitrogen cycle seems to say that once there are nitrites, there shouldn't be any ammonia, and once there are nitrates there shouldn't be nitrites. My tank seems to be backwards, in that there have been nitrates there from the beginning, and although the nitrites now seem to be spiking, ammonia is still present.
This brings me to my next concern. I've also been testing the params of the tap water every time I do a water change, and to my uneducated mind they seem peculiar. Ammonia seems to be a fairly constant 0.25. I don't know if this is usual for tap water. What's the result of adding it to my tank? Surely it would just maintain the ammonia levels? The tap water shows as having 0 nitrites, but nitrates at 10ppm, which, again, is the same as the tank. This makes water changes seem a little pointless! At this point I feel like all I'm doing is reducing the nitrites with water changes, as the ammonia and nitrates are the same. The other thing about the tap water, is that the PH fluctuates between 8.0 and 7.4, apparently every other day or so. The tank water now seems fairly steady at 7.4. Will this water have a negative effect on the tank/its eventual occupants?
I appologise for the essay! Would really appreciate some more experienced opinions.