Something odd going on... the KH is rising.
Uh-oh... I used some pond fertilizer tablets that were in poor shape- more like powder to granules, not tablets any more. Dusted it on the bottom, under the substrate.
Fishless cycle chugging right along. Ammonia and nitrite readings high enough to grow plenty of bacteria.
Nitrate, too, but I add fertilizer for the plants, a blend that includes N. (plus the pond ferts!)
I may have over done the ferts. Gotta move more plants into the tank.