Hi Viv
I find it very practical to be able to lift the whole wall out of the tank, sometimes (trimming fx), so I use a very stiff metal-net. Stainless ofcourse. If a small tank one piece does it - larger tanks may need several "panels" side by side. This usually will stand without sucktion-cubs, fx being squeezed inbetween gravel and back-glass.
Moss is spread out, covering the net. Longer "threads" are easier to work with, than very short ones, since I then roll thin fishing-line all around the net. Both left/right and up/down. On large pieces of net, it's needed to tie some of the cross-sections of fishing-line on middle-part to the net. This is done simply by short pieces of fishing-line put through the net, catching tbe fishline-cross, put back and tied (modern fishing-line can be tied, yes ).
- BUT Viv.......... what usually ruins a moss-wall is the lack of suffucient light in upper, lower and side-parts of the wall. I only do moss-walls in tanks, where I know, I have this light available. Very few "standard tanks" have that. It's worth to mention, that you must trim the wall, same way you do your hedge......lower part must be broader than upper, so upper don't shade lower ( - or you just let the panel lean backwards!!! )
This is not the cheapest method, I know 🙂...........but it makes a nice moss-wall, that's easy to maintain.
Mick.