This one is actually about 4 weeks old, and is still tiny! The other one is doing pretty good at the moment, but this one seems lacking. Growing under fluro in seed and cutting potting mix (no slow release rubbish, just soft loamy stuff). Soil ph is around the 7.5 mark on my crappy soil ph kit, water is rain water, but around the 6.4 mark on my aquarium ph kit. I have given this one a 1/4 mix nutes about a week or so ago, which I think has made little impact. The redness appearance was there prior to nutes. I was hoping they would have helped! This and the one in the background are essentially raised identically, but this one is struggling. It's hard to take quality pics with detail on such a small planet. Fire away with questions and comments!