Here are some pics I dug up today. I had the species like the first one you posted.
The pics dont really show the color well but you get the idea. They first started out right next to each other then I decided to put the purple one back in a shaded cave and traded the orange for a rbta. They make great additions to areas without much light. When I moved the purple one thats when I realized they grow really long tubes. I wonder if what the purpose of it is? Anchor or would it maybe try to move to the other ends if it wanted to?