Cloth objects dont collide with anything unless you tell them to. So by default they wouldnt collide with the floor.
Likewise they also dont collide with cloths on other solvers so by adding many solvers they wouldnt collide with each other. So just select the cloth object and do nSolver -> assign solver -> new solver. Thsi is probably what you want because you would need to do a bit fo mathematical trickery to get collision layers to work since youd need to have a range thats within the floors layer but objects not being within other range.
Likewise collision layers MIGHT work. But please note collision layer the separation between the numbers needs to be more than the collsionLayerRange in the solver node for them not to collide with each other.