Nothing Smells so Sweet as a New Holding Tank

The new holding tank arrived on Monday, June 20, 2022. We had thought that the original tank was intact and just the fittings and hoses needed to be replaced, but we later learned that the tank was cracked.

After researching options, we found the International Nonsuch Association tank replacement program which offered a nearly identical replacement tank at a competitive price. When I realized that the price included shipping, I felt this was a great deal so we purchased a new tank.

Let’s look at the condition of the old tank and then take a look at the new tank.

Old tank

The old tank was, well, old! It was discolored and had become brittle. Previous issues with leaking fittings had been mitigated by pasting epoxy putty around them. The photos below show the condition of the old tank, fittings, and deteriorating hoses.

(If you notice some hair in the photo of the tank before it was removed from the starboard quarterberth, that hair was from the previous owner’s dog who was a constant, treasured sailing companion.)

You can see that the discharge hoses were in pretty rough shape and how the fittings had been patched to try to keep them from failing. The crack on the underside of the tank at the discharge hole was the surprise that triggered my purchase of a new tank. Up until that moment, I thought we were just replacing fittings and hoses.

New tank

The new tank arrived quickly from California. We found the crack in the old tank on June 7th and I ordered the new tank on June 8th. It was shipped on June 14th and arrived on our doorstep on June 20th. That is pretty awesome for a replacement tank on a 40-year-old boat. I am thankful for the International Nonsuch Association!

The great news? The tank fits in the starboard space. That is a win.

The bad news? The tank is not an exact replacement. The old tank had one vent hole and that hole was smaller. The new tank has two vent holes (one aft, one forward) for one-inch vents, so twice as many vent holes and larger to boot.

However, this is not a big deal. My plan is to use just the forward vent. My concern is that venting to the stern might bring odors back into the boat from the backwash during sailing and motoring. I’ve heard from one owner that this happened to him. We use an enzyme product in our tank so my expectation is that odor is not going to be a big issue for us with a single vent, plus the one vent line will be bigger than before.

Installation

I have placed the new tank in the boat to check for fit but it is not installed. The aft vent hole needs to be sealed. The toilet needs to be connected and a new, larger vent line run to the vent on the side of the boat. I’m hoping for an open port through the hull so that a simple back flush with water from a hose will help to clear any debris or nests that might get in there.

Until the installation is complete, we are happy to have a Thetford Porta Potti 365 on board. It is a simple unit that just works. While the Nonsuch 26 is not a big boat and the Porta Potti definitely gets in the way, it should be a reliable backup when we take longer trips.

I will update this post once the tank installation is completed.