Ill try cranking the CO2 up a bit.
By the way i just did a pH/kH check - pH = 7,0 ; kH = 8,5dH
That should give me around 25ppm CO2 right?

Tomorrow ill try another reading at the same time and see if thats doing a bit.

- Just found thread algae today... Never happened in that tank before.

The tank needs a serous trim to cut away some of the bad glosso and rotala.

Im considering pulling everything up, vacuming the top of the bottom and replanting...

Could it be a NH4 related issue, due to a nasty mess under the glosso?