Bark background ??

[jenlynn]

My son got me a whole bunch of hemlock and doug fir bark slabs. They are anywhere from 3in x 6in to 5ft x4ft long. They already have moss, tree lichen, and some pieces have small ferns. I want to glue the to the back of my 75 gl and 110 gl toad tanks I'm making. I will pin the ivy type plants to climb and will be attaching broms to them. They have been in my garage for 4 months(husband starting to complain.hehe) next to my plant growing shelves/lighting. I mist once in a while to keep plants alive on bark. I know you are supposed to soak in light bleach water then clean water to sterilize wood, but how can I do this without killing plants. Could I spray bleach water on then rinse or would that not be enough? Any advice would be great. thanx