I recently installed a marble floor and the existing toilet flang in place is to high. When I installed the new toilet rocks because there is play in the flang. What can I do to so the toilet doesn't move when I sit on it?

What material is the flange and raiser? Back to you, Tom

Attach flange to the floor. Drill holes into concrete slab and secure ring with several screws. Flange has to be solid and have no movement to it. Then, insert brass toilet bolts, install wax ring and set your toilet. Tighten bolts to keep bowl against the floor. Now, take caulk and squeeze bead of caulk into the gap between the bowl and floor. Smooth with finger and clean excess of caulk. If you use silicone caulk, clean with denaturated alcohol. If you use latex caulk, clean with wet rag. You can also use grout instead of caulk. Let dry. Now, toilet will not rock.

Let us know how you did...