Thanks Luis,
That's exactly what I've got at the moment, in soil in a bonsai pot. I found it very slow just in the pot, but it's been in a tuppaware pot as well for the last 2 weeks and it's gone mad. Spread about 500x quicker with the higher humidity, no exaggeration. It is pretty slow in the tank, too. I'll trim one section right back and see how we go.
Cheers,