Hi flygja, thank you for your comments. I don't know exactly why these plants turn red, surely other members do. But I can give you some info from my experience. When planting stems from the same plant in two different tanks that follow the same dosing approach, one working with SMD cool white LEDs (20 lumens/litre) and other with T5 Philips 865 fluorescent tubes (1wat/litre) i notice that they grow green in the former and reddish in the latter. Also in the latter I can observe that the closer to the water surface (and also to the light source) the more pigmented the leaves are. Perhaps light quality or quantity can have an effect on the colour pattern, but this is not a true experiment at all (indeed, it has nothing to see with an experiment, light sources are not comparable, tanks are different, etc, etc,..., it is just an observation) so please take my comment just as a suggestion. I also try to keep iron at 0.2ppm, but I don't really know if this is affecting colour. Surely there are many factors involved, including genetics, and I'm sure that the experts in the forum can help us in understanding what is happening in our tanks.Beautiful tank! I've been trying to achieve the same effect for a few months now without success. I also have L.repens and P.palustris, but they're all green in colour in my setup 😕