Ther archers are finally back, out of their hideouts. The trick was, apparently, to give them some fun, i.e. some CRICKETS! I got some huge ones a few days ago, they're long gone, but since then the archers never went to hide again, and stay alert all the time for some more to come. Great.
The "good" mangrove has now 6 (!) leaves, and still only small roots, whereas the "bad" ones have no leaves at all (or better, they lost all of them), and a great root development. Unbelievable.
The Vallis are not doing very well, they keep on the yellowish side, even the new leaves now, but they do keep generating new runners, which is, I believe, a good sign. I only set a few tablets of Tetra Plant Crypto fertilizer at the end of July, when I settled the plants into my bare sand substrate, and then randomly provided small amounts of liquid fertilizer. I'll try to go for more. Pity the Fe test I bought just doesn't read anything else than 0 mg/l...