To be more precise: my tank is ten years old. I do water changes weekly. No new tank mates. 2 snails, 2 panda corys, 6 tetras, 2 kirbensis cichlids. pH: 7.5
Ammonia: 0
Nitrite: 0
Nitrate: 20
gH: high as test will read. It’s always been that way, for many years.
My tank is very well established...