hi tom,
I indeed have the ADA AS already in my appartment. It is just that the new tank is not ready yet. The glass has been glued together, now the frame etc. I think it should be ready within 1-2 months.
About the plant species, al grow good/great without the excel. The melting of the tonina has definately stopped. The tonina and eiocaulon is now a very easy plant to me. In regard to plant growth I think the biggest problem is that my glosso is is growing vertically (wonder how that comes

). But the solution was easy, I replaced it by elatine. An easy plant that I really like is Hedyotis salzmanni. Very nice for scaping!
I will keep up the waterchanges and cleaning. And on your advice I indeed use TMG. I use 25-30 ml per week. At 21 ml I saw that the plants were a bit yellow. More iron worked, but I see that more TMG improved the health even more. guess it wasn't just iron that was a bit short.
edit:
I forgot to tell that my lights are on at aroun 2 pm. Although I close the curtains there is of course quite some light in the room. Could it be that plants are trying to assimilate before the TLs are on? Then a CO2 lack can definately occur. I do see that the proserpinaca palustris cuba has curled leaves in the morning, but not in the evening. Does this indicate a lack of CO2 in the morning?
@ hani
I use normal T8 in the colour 830/840 from philips. I have two tubes burning for 10 hours and 1 tube for only 1.5 hour as a light peak.