I have a double kitchen sink that was clogged in November. I tried to use a plunger, without success to clear the clog. We finally called a plumber to come out and snake the drain. During this visit, he sold some Bio-clean to us. Less than 2 months later, we have the same problem again. The same plumber came out and repeated the process. It backed up before he left. That evening, he had us pour some acid down the drain. Now he want to come out and use a camera on the drain. He thinks that we may have a sag in our pipes. So for over $400, we still may no solution to our clogged sink. Our house is 8 years old.