The black plastic pipe is more suited for use in RV applications then the standard white PVC. As I recall. It handles vibration better. Thus it's not just a color thing. It's out there. Just will take extra searching. Bob Dunahugh
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From: Bob Dunahugh
Sent: Thursday, July 5, 2018 12:03 PM
To: gmclist
Subject: RE: Hello. Just wondering
Scott. Glad you signed up. For me. It's been a bit of a love/ dislike relationship. Not hate. But I'd do it again. The Royales are great. As you have more options. I made mine so I can dump just the black. Ore just the gray. When dumping both. I use the gray last as a rinse. Also I can dump with the 3" hose. Or the macerator. The main reason that I have the 3". Is that I can fill the black tank with lots of fresh water for a rinse. Then open the 3" for a stronger/faster final rinse. I also put a rinse spray nozzle in the black tank to create more turbulence during the dump/rinse. I've checked the black tank with an inspection camera. It gets really clean. The Bob Done-a-hug
________________________________
From: Bob Dunahugh
Sent: Thursday, July 5, 2018 12:03 PM
To: gmclist
Subject: RE: Hello. Just wondering
Scott. Glad you signed up. For me. It's been a bit of a love/ dislike relationship. Not hate. But I'd do it again. The Royales are great. As you have more options. I made mine so I can dump just the black. Ore just the gray. When dumping both. I use the gray last as a rinse. Also I can dump with the 3" hose. Or the macerator. The main reason that I have the 3". Is that I can fill the black tank with lots of fresh water for a rinse. Then open the 3" for a stronger/faster final rinse. I also put a rinse spray nozzle in the black tank to create more turbulence during the dump/rinse. I've checked the black tank with an inspection camera. It gets really clean. The Bob Done-a-hug