:iagree:If your ammonia is 2ppm,do a large water change. I would get some Prime,and some Seachem Stability too.
Changing substrate, water and filter media is basically setting up a new tank and restarting the cycle process. Bacteria in your filter will prevent this. Or the bacteria on your gravel. Thats why you can change one or the other w/o a spike in NH3( water, filter, or substrate). There is enough bacteria left behind to compensate for the loss. By changing all 3 you eliminate 99% of your population and it will take a few days to re-establish unless you COMPLETELY scubbed it out, then almost a month.How?
Agreed. Making mistakes is part of the learning process so don't be so hard on yourself after all you are looking for answers and taking action to correct it.The best thing to do is stay calm and stay on top of waterchanges until ammo is under control.
The substrate change alone could cause a mini cycle combined with the filter change and that's what most likely happened.
I think most people in this hobby has done this at least once, I know I have.