Composting head - R23

[wndwalkr]

Has anyone swapped out to a composting head in the R23? Would make the fresh water last longer and maybe even convert the holding tank to a fresh water tank… we are looking at getting a 23 but the small tankage has us concerned. Last boat was an R31.

 

[Sweet_Pea]

We put an Airhead composting toilet on our R-25 classic. Since we bought new, we never used the holding tank, so we were able to use it for back-up water supply using a Y-valve to switch the source. Swapped the waste cap for a second water cap.

The composting head could get through the summer before we had to empty it and we bought a second urine tank to stretch to about 5-6 days in between emptying (2-3 days per urine tank for 2 people.) We prefer a composting head over pumping out. It worked really well and we never had pump out anxiety. All paper went in the trash. Between uses, a strong vinegar solution in a spray bottle helps disinfects the bowl. (Can’t use cleaning solutions because they interfere with composting.) Never had any odor issues over the 10 years we owned the boat.

A hose vent ran to a fan installed on the stern gunwale, which we wired directly to one of our batteries. The fan needs to be powered 24/7 to keep flies out.

The boat had been built with a marine toilet installed. Since the raw water line running from the thru-hull/seacock to the marine toilet was still there, but unused, an engineer friend suggested modifying it to be able to flush the engine with fresh water in the raw water cooling system instead of sea water.

A Y-valve sits inline on the marine toilet supply line. One leg still connects (via the seacock) to the sea water thru-hull. The other leg goes to a hose barb/connector with a standard garden hose. By closing the seacock and opening the Y-valve to the hose side, fresh water from a dockside hose feeds into the engine's raw water intake. Make sure the engine is cool and off before flushing and that water is flowing when the engine is running.

 

[GTilley]

On my new 2026 R25, we took the old toilet out and put a Modiwell R1808 Dry Flush Toilet. Zero need for water. You could hardwire into the boat, but we didn’t do that and just charge it. We’ve had it in use since early June of this year, and have charged it once in all that time. https://modiwell.com/products/modiwell-elite-r1808-rv-toilet-waterless-dry-flush-fixed

It’s absolutely amazing, and I highly recommend. The customer service is extremely fast and thorough, as well. We haven’t added the black water tank to the fresh water supply just yet, but we plan to do so whenever we get into longer trips (just weekend warriors now, we have yet to empty our fresh water tank by the end of the weekend).

 

[serendipity]

On the boat we had before our 2023 R27OB, which was a Westsail 42 ketch, we had 2 Nature’s Heads. They worked wonderfully.

We considered replacing the factory toilet with a Nature’s Head or similar. However, the throne height was too high for comfort and the gymnastics needed for emptying seemed to need more space.

Final decision wss to leave the head factory.

That being said, dedicating toilets work and work well and worthy of consideration.

 

[Sweet_Pea]

On my new 2026 R25, we took the old toilet out and put a Modiwell R1808 Dry Flush Toilet. Zero need for water. You could hardwire into the boat, but we didn’t do that and just charge it. We’ve had it in use since early June of this year, and have charged it once in all that time. https://modiwell.com/products/modiwell-elite-r1808-rv-toilet-waterless-dry-flush-fixed

It’s absolutely amazing, and I highly recommend. The customer service is extremely fast and thorough, as well. We haven’t added the black water tank to the fresh water supply just yet, but we plan to do so whenever we get into longer trips (just weekend warriors now, we have yet to empty our fresh water tank by the end of the weekend).

Hadn't heard of a dry flush toilet...thanks for sharing! Seems like lower maintenance than a composting toilet.

 

[Hamster]

I know someone who did that in an R23. She sold the boat a couple of years ago so is likely not watching this forum. It didn’t sound like there was any particular issue with the change.

 

[GTilley]

Hadn't heard of a dry flush toilet...thanks for sharing! Seems like lower maintenance than a composting toilet.

It is! I wish I could figure out how to add pictures on here, but while it’s a little taller than the raritan toilet, it takes up the same amount of space. There’s no smell, ever. EVER. We didn’t need to add a through hull for exhaust.

Before using the toilet you put in a powder that helps to ‘gel’ your waste so it’s not liquid, and helps to control order until you ‘flush’ the waste and it seals. It’s just my husband and I, so to save on battery/bags, we ‘flush’ after 3-4 number 1s, or any number 2s.

The bag wraps and seals the product, and drops it in its own trash. You simply take the bag of trash out and dispose of it. There’s been zero leaking, zero fuss, zero water. And again, we’ve charged it once this season. And 2.5 months later, we’ve changed out the bags (it comes in a roll, like a garbage bag roll), one time. It says a roll is good for 20 uses, but we’ve easily sealed double that amount, so they are underestimating the amount of usage.

We did the same as you with barbs to close up the water lines for the toilet, but because we don’t fish, we just closed down the intake valve for the salt water wash down and the toilet, just to ensure no water can get in.

The toilet is $700-800? Sure, it’s a big upfront cost. But honestly, I’m hard pressed to figure out how they could make it better, and I’d buy it again in a heartbeat.