[strath76]

There is no doubt that clay pots provide benefits to plants. It is often recommended to use these for plants such as Darlingtonia and Heliamphora that require cool roots. You are right about the salt leaching through the pots and you should never reuse a clay pot for CP's for this reason. If you are starting with a new pot then the contamination should only be a problem if your water quality is poor (i.e. contains salt and other minerals). If you are using pure water then salt should not be a problem.

If you are trying to keep the roots cool then putting one clay pot into another larger clay pot can work quite well. You simply fill the gap between the pots with sphagnum and place in water. This provides an increased buffer for heat build up and you still get the benefit of the evaporation cooling.