Mom wanted new sinks, and where we had two identical bowls on the old one, the new one has a bigger left sink and a smaller, shallower right sink. Ever since it's been installed, water drainage down the left one has been horrible when the right one is being used to wash dishes. I have to break the drain to let air escape so the left bowl drains normally. Is there a way to fix this? I figure a valve that lets air out but not water might work, but I've found nothing like it. Here's a photo of the current set up.