some say 1:10 bleach dip for 1 minute is good, but I've never had any problems with just gently scrubbing the leaves with my fingers over running water at room temp. Also be sure to prune all the dead and dying foliage before introducing into the tank.
Pots: it's ok to keep the plants in the pots but again, gently removing the rockwool from the roots under running water will ensure the plant's roots have ample room to grow and thrive.