I have done a wall, but i guess my lighting (and no CO2) or type of moss i used didnt turn out so well, as there is some browning when looking from the front, though you cant see it from sides or top. What i should have done for my low tech setup is java moss only and no other type of moss, instead of weeping moss.
Anyways, just to give you another way, its much more expensive, but gives a great look when the moss is not fully settled in (as that could take alot of time), and doesnt take too much backspace room, and if all the moss decides to die on you, the wall can still look descent as a background, and no succion cups involved!
- 1 White Canvas from Michaels or from Wallmart (the ones that Fishfur mentioned)
- 1 Black Plastic Pet screen (this one is safe, and is like rubber, nice mesh size that alot of black is viewable.
http://www.homedepot.ca/product/petscreen-36-inch-x-84-inch/982445
- Magnets (both submersible and none)
http://www.kjmagnetics.com/proddetail.asp?prod=D84PC-BLK
http://www.kjmagnetics.com/proddetail.asp?prod=D82E
- fishing line, i got a green one from Canadian Tire
- alot of MOSS (depending on your lights, chose the most beautifull that will go with your system)
So first cut to size the canvas and black screen.
Then sow them togheter using fishing line. The purpose of the canvas is stability, specially for the next step. Why the black screen, for beauty, white background may not look too great in many setups.
Then sow the moss on the black screen side (the canvas side will face the aquarium wall)
Then use magnets to hold it to the wall. The rubber magnets will be for inside the aquarium, and the coated ones will be for outside it.
There, No gap in the wall, straight flush finish, can be like a blackwall when no moss (black wall is much nicer though), you dont see the white backwall so much, you dont have to wait for the moss to grow through home because the moss is right on the viewing side (ie not sandwiched between two screens) , easy to remove, magnets could also be used for other purposes (for example, i use some to hold sliced cuccembers), etc...
Comparatively, it is much more expensive, but, i like the advantages.
Whichever way you go, you will require: ALOT of patience!!! Good luck