Forum Discussion

Explorer

Aug 03, 2018

Running Dual Black Tanks.....

Howdy

I'm designing a compact travel trailer which is focused on extended dry camping and crossing the USA.

I'm liking the layout that I have but due to small size I've got the combo shower/toilet in the front of the trailer. This is fine except for I don't want the 42 gallon black tank in the front of the trailer. For weight balance I need to move it aft.

Though I have been thinking about a composting toilet, sounds to me like they can be a real hassle, especially if west of the rockies.

So I'm coming up with a plan to make this work, bear with me....

I'm thinking of placing a small black tank directly under the RV toilet. Probably something in the "several gallons" range. (they do exist)

Plumb that black tank to a permanent marine-style macerator pump.

Plumb the output of the macerator pump to my main black tank located near the axles.

When small tank is full, flip the macerator switch and pump it out into the main black tank.

Main black tank will drain just as all normal black tanks do.

I'd probably also put a 3" drain drop on the mini tank just in case there are problems it can still be emptied and flushed for "service".

Anybody done something like this? Comments?

Thanks

CM

24 Replies

Home_Skillet
Explorer II
Aug 03, 2018
You can look at horse trailers with living quarters. They make use of a small space.

There are flat black water tanks that hold several gallons.
Google is your friend.
mat60
Explorer
Aug 03, 2018
Will this build also cost you more than just buying a RV? I thought about a build a long time ago with a 8x14 carog trailer.
Colonel_Monk
Explorer
Aug 03, 2018
Howdy. Yeah, I wish it was that simple. It's only a 14 ft x 7'4" wide inside area. I have already my freshwater tanks over the tandem axles, Dometic full size reefer over one tank and closet over the other.

If I put the bathroom in the middle then the freshwater tank would have to go to the front which doesn't solve the balance problem.

With the current floorplan I will simply be shifting the weight from the fresh water tanks to the waste tanks and more or less keeping the balance the same.

I do realize it's a pain, but seems doable.

Fact is, the idea of this whole RV project will seem unnecessarily complicated to some, it's certainly easier to just buy an RV which is why not many folks decide to build one.

I have specific wants that just aren't covered by traditional RVs. That said, there are downsides too to swimming against the current.

thanks,

CM
donn0128
Explorer II
Aug 03, 2018
Sounds like a whole lot of effort. Since your in the design stage, why not simply move the bathroom to the middle of the trailer?