Thanks both, mine is twisted, so I recon definitely vallis.
Fingers crossed it starts taking root.
Tank looking good atm, but could all go down hill shortly.
Also have a question re Java moss. Tied it to some twigs to look like trees, and it looked great, but as it's grown it just looks like a mess of green fluff. Not attractive at all. Any tips? Or should I try a different moss?
I got a freebie of a liverwort with my moss, and it's doing well and is quite attractive, also tied to a twig.