You are WAY, WAY, WAY off on the amount of PS that you need. I have never seen a Swiss recipe that calls for "large quantities". The gas produced by a teaspoon per gallon will explode the rind and the cheese will fail. The rind drying out and cracking is something you have control over. You should re-read your recipes and do a little more research on the forum. Tons of discussions on Swiss and rind management.