If its worth posting, is that Tablets are not designed for super strong wash action. I've found in my DishDrawer that Fairy tabs cause a ton of foam, as do dishwasher cleaning products (I cite Finish here, since I had to run at least 5 extra rinses afterwards to remove the foam. The stuff also destroyed my drain filters!)

You may find that your machine is underfilling ever so slightly the pump is getting enough air to whip up some froth. Try using only one detergent wash and perhaps adding some extra water into the machine before the detergent is dispensed during the Main-Wash. The issue may also be a built-in Rinse-Aid component, which I know causes frothing at lower temperaturs (Rinse Aid often foams at low temperatures, according to my DD's manual).

Just try using a good quality POWDERED detergent, such as Bubble Bandit, Cascade Institutional, or any detergent you prefer where you've added phosphates for "good measure." I can say phosphates and soft water may not mix here... Our dishwasher detergents still contain >30% Phosphates in most cases (Finish, Fairy, Morning Fresh, Kwit, "IGA Brand" etc.), and I'm wary of testing out "Eco" tablets, since my machine's Eco cycle doesn't give the 3 Rinses I prefer...