Soopaman
Wants a Hamata
Does your clay run all the way to the floor of the tank (not just the soil level)? This helps the clay soak up enough water to stay well hydrated. I realized in my own designs that any clay not conneceted to the main mass will dry up even with misting, It must be a continuous mass.
But no, I don't have drying problems unless I quit watering intentionally. When I start them up I plant it heavily from the beginning with 1" clumps of moss and plant cuttings scattered about the background and I gently soak it every day with a garden sprayer until the moss & plants root and spread. I use one of those 1 gallon pump action types used for fertilizers or pesticides (make sure it's new and never been used for those) you can adjust the nozzle from a solid stream to a gentle mist and just squeeze the trigger and flip a switch to keep it on to get a good soaking "rain". This device is the best for soaking everyday, the hand mister needs a lot of pumping to achieve the same level of wetness.
Yes, one section of the clay does, the back wall. The right upper side wall, does not, unfortunately, as the waterfeature separates it from an direct contact with the portion below it. I guess that is why I am having problems with that section. I will say though, that I wouldn't want to have the clay connecting with the waterline without a heavy bit of substrate in front of it, as the clay I made seems to just fall apart when put in large amounts of water. I suppose there is some sort of happy medium to be met with it though.
I am going to order a ficus and this nice coppery pink Monochaetum sp. Ecuador for putting on the wall. I have some more of the clay left and I will try to cut away some of the dry stuff on the back right and replace it with fresh wet stuff when these plants come in. Oh well, probably should have thought on some of these things before hand, but it is my first big project, I'll be a lot better prepared when I do another.
And I'll have to get one of those sprayers, sounds like just what I need to help keep this from drying out and becoming a disaster