Hmmm. That may explain why I started to have hair algae all of a sudden.
My tank is moderately planted. I have been dosing NPK and TMG regularly and the plants grow steadily for a while. I noticed lately that pH always stays around 6.5 (a 6.8 will open the solenoid) and co2 never get into the tank because the solenoir always stay closed.
I have java fern and java moss tied to the driftwood so I guess it takes a few w/c to get back to normal. Thanks, Rex. Pictures of my tank