I bought the 5 stage system from RODI and it comes with the hose adapter. I tried connecting it to my bathroom sink directly to the cold water line. From my understanding the cold water connection is 3/8 so I bought a 3/4 male to 3/8 female adapter. The adapter fit under the 3/4 side but when I connect it to my cold water line it seems like it’s big…. What did I do wrong here?