I have a 2017 Salem hemisphere 300bh I bought 2 weeks ago. It is our families first camper. The camper has 2 sewer drains. There is a grey handle and a black handle for the front pipe and two grey valves on the rear pipe. I have determined that on the rear pipe one valve is the inside kitchen and the other is the outside kitchen. The problem is that there is a grey handle and a black handle on the front pipe. It appears that the shower, toilet and bathroom sink are all going into the black tank. And the front grey tank handle drains absolutely nothing. What is going on.