Center split bath - black tank

[MWairstream]

We are renovating our 1969 25’ Tradewind. We’ve had her for a few years now, and only recently have we found more time for the reno. As you can see by the attached picture, we built gantries and did a shell off. We are almost done reinforcing the frame and painting it with POR15. Our plan is to full time for a year starting this summer, so we’ve got our work cut out for us.

I’ve searched the forums and have read so much, but I feel like I can’t find the exact answer. We are moving our bath from the rear to a center, split bath. We are planning to add a grey tank in the frame in the area of the axles, and a black tank above deck with a low profile toilet (to keep from freezing if we venture into those temperatures). My questions are:
1) I am looking for the actual black tank that I can use above deck in a center bath. Has anyone done this setup that could recommend a specific tank?
2) I’ve read that the grey tank should flush through the black tank. How can this be achieved with my desired plan?

Thanks!
Marta

[rugjenkins]

With the setup your talking about black above gray you would need a pump. What most are talking about is when you empty the black you then follow with the gray to clean out the stinky slinky. To get the solids out of the black just open the toilet and pour in more water to help rinse out. There are also water wanes to help clean the black. Using the gray to pump into the black in your case would require a pump and it's not really needed. The black is smaller than the gray and could over flow if not careful.
I've done the same on mine- relocating rear bath to the center. I was going with the same idea with gray in rails and black on deck but decided to place both in rails.
Hope this helps, have fun😄

[rugjenkins]

I think I have the original tank that was above the floor. I'll check and see if I still have it. If so you are more than welcome to have it. It was still a good tank

[MWairstream]

Why did you decide to go with both tanks in the frame? We are nervous about it freezing if we are boondocking.

[toastie]

A above custom tank can be very expensive. I installed 3 tanks in my 1955 22 foot Airstream below with the black tank in the center. Will post a few pictures.

toastie

[Lance M]

Hi,
When camping in the cold, the first thing to freeze is the outlet valves under the trailer. It takes a long time in very cold weather to freeze the contents of a tank in the belly pan.
There are many ways to design a black and gray tank setup. I kind of like the above the floor black tank, but it really can be done either way.
I have installed a couple of above the floor black tanks. I normally get tanks from Pelland Enterprises. They have just about every tank out there in their catalog.
http://www.pellandent.com/RV_Product...CategoryID=156
Good luck!

[rugjenkins]

I wanted the toilet on the floor not up on a pedestal. Its just personal preference. There are tank heating blankets one can install on the bottom of the tanks to keep them from freezing. Some even pour some antifreeze to help overcome that issue. Many options😄