Amazingly beautiful! I can't help but wonder how big the clear box they are in is. Your photos certainly make me want to grow the genus. Thanks for the pics!
Could it be that the plants are receiving a level of light intensity/duration that puts them at a threshold between the green coloration and the red? This would mean that if the amount of light they get was increased they might all turn red. 'Just a thought.
Yes I agree with Mark beautiful plants. I will have to check my local Lake (White City Lake) Trenton NJ. It is full of aquatic growth. Possibly some aquatic carnivores. I will take pictures and report back.
The box is completely transparent. The plants are left at the windowsill (filtered light, no direct sunlight) and I haven't looked at them in a while, so I am pleasantly surprised that they have coloured up. The end further back is more green possibly because it is further away from the light source but the answer I do not have is how these plants turned red but not other red forms. Also, I have the same form in another box next to it (same amount of light) and it remains green.