I am getting so frustrated.
I have a 20 gallon tank with 3 white-skirt tetras, 3 black skirt tetras, 5 orange von rios, and 5 ghost shrimp. It's a fully planted tank, with lots of different kinds of live plants. To clarify before I begin, all of my fish and shrimp are showing no signs of stress, and I haven't lost anyone during this hectic week. Alright now.
About a week ago one of my black skirt tetras was found with a couple of ich spots on his tail. I turned up the temperate in the tank to about 81, and put a bit of salt in the tank. I was told by several people who knew from experience, that if my fish are fine, water quality is good and it's only a couple of spots, the fish should be able to fight the ich off on their own. It's been a week, and although a couple of spots will come and go, it does look like they're fighting it off.
I did a 25% water change last night. I mostly wanted to start getting the salt out of there. Again, nothing out of the ordinary.
I check my water almost every day, and so when I checked my water today, it showed that the nitrites in my tank are quite high. This took me off guard, because I did nothing unusual during my water change other than change the cartridge in my filter, which I rinsed off very well in the sink before sticking it in my filter. (It does have carbon in it.)
What did I do wrong? And more importantly, what can I do to get those nitrites down at the moment? Should I put some more conditioner in the tank? (I use AquaSafe)
Please help... I'm getting pretty fed up with this tank.