i have a very stupid question but it's critical to confirm. I bought a used Vortech MP20. The directions clearly indicate a pad is needed between the glass and the dry side. Is that really necessary? I ask because i don't have one. Second question. On the wet side there is a pad between the glass? because the one i got sure does and it's adhere to the wet side. It does not seem right, to have a glued pad in the water.. thanks