Just tested nitrite tonight and it was off the chart again. Guess increasing the flowrate was the wrong thing to do.
Cranked it back to 1 drop per 7 seconds.
I have to wonder that something's wrong with this scenario. There must be too much O2 coming into the unit preventing a proper anaerobic zone. Next time I'm at Home Depot I'm going to buy maybe 50' of 1/4" tubing to add to the inlet. Not sure what's left to try after that.