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That does sound a bit odd.
Did the nitrite drop to zero from a high level all at once or did it slowly go down to zero? And which tester are you using?
I've looked at my cycling record from a few years ago and mine dropped from over 5 to zero between day 40 and day 42 (testing every second day), but my ammonia had been zero since day 28. So nitrite can drop to zero suddenly but it's the ammonia reading that is puzzling.
Have you checked your pH? In Scotland you will most likely have very soft water and if the pH had dropped very low it will affect the bacteria.
That pH shouldn't have stopped the bacteria, but it is quite low for cycling - near 8 is the optimum for bacteria growth. It does mean that your cycle will be slower than one in a hard water area though.
Keep an eye on the pH, and give it a few more days.
That pH shouldn't have stopped the bacteria, but it is quite low for cycling - near 8 is the optimum for bacteria growth. It does mean that your cycle will be slower than one in a hard water area though.
Keep an eye on the pH, and give it a few more days.
It's because you have very soft water so you also have low KH. Nitrite is acidic and KH stops the pH dropping but when there is very little KH, it gets used up then there's nothing to stop the pH falling.
There is something you can do just for during cycling. Add bicarbonate of soda. This will add KH to the tank. But it will also add sodium which is not good when there are fish in the tank so once the tank is cycled you'll need to drain the tank down to the substrate to remove it. You may already have some bicarbonate of soda in the kitchen; if not it's in the home baking section of the supermarket.
Use 1 x 5 ml spoonful for every 50 litres tank water. Take a bit of water out of the tank, dissolve the bicarb in that then pour it back into the tank. Wait half an hour then test pH again - it should have gone up. Test pH every time you test the rest to keep an eye on it.
At the end, once you've done the huge water change and got fish you'll be doing weekly water changes of over 50% and this will replenish KH. But with your soft water you need to keep soft water fish so even if the pH drops with fish in the tank the fish will be fine.
It's because you have very soft water so you also have low KH. Nitrite is acidic and KH stops the pH dropping but when there is very little KH, it gets used up then there's nothing to stop the pH falling.
There is something you can do just for during cycling. Add bicarbonate of soda. This will add KH to the tank. But it will also add sodium which is not good when there are fish in the tank so once the tank is cycled you'll need to drain the tank down to the substrate to remove it. You may already have some bicarbonate of soda in the kitchen; if not it's in the home baking section of the supermarket.
Use 1 x 5 ml spoonful for every 50 litres tank water. Take a bit of water out of the tank, dissolve the bicarb in that then pour it back into the tank. Wait half an hour then test pH again - it should have gone up. Test pH every time you test the rest to keep an eye on it.
At the end, once you've done the huge water change and got fish you'll be doing weekly water changes of over 50% and this will replenish KH. But with your soft water you need to keep soft water fish so even if the pH drops with fish in the tank the fish will be fine.
I would add the bicarb and see what happens over the next couple of days. I know that a very low pH stops bacteria multiplying, but I don't know if that is both bacteria or just one of them. It is possible that low pH affects the ammonia eaters more than the nitrite eaters. Increasing pH by adding bicarb will hopefully allow the ammonia eaters to start again. If it doesn't we'll need to think of something else.
The worst that will happen is that you'll have to drain the tank and refill it, adding bicarb, then dose 3 ppm ammonia and go from there.
Yes, post as many questions as you need to
My tap water KH is 3 dH and when I did my first fishless cycle years ago using the old "add ammonia every time it drops to zero" method (which makes a lot of nitrite) I too had a pH crash. Bicarb solved the problem. So when I did another a few years later to see how the new method on here works, I added bicarb at the start and had no problems.