I have very little new growth in my tank too, except for some new plants that I got from a different tank. Could be that they're still using leftover stored whatever mineral is lacking, from the old tank. I have had them for at least 1-1/2 months, though.<br />
I dosed the tank with Potassium last Saturday, but only have seen a small amount of growth, and my Sword's leaves are continuing to deteriorate, brown tips and edges.<br />
pH 7.4, KH 2, GH 5, Nitrates 20 after 25% water change.
I like the layout of your tank!