Let’s Review a Product with…SCIENCE!

Stormageddon 2016 turned out to be much easier on us in Tacoma and Lakewood than predicted. Nationally, forecasters predicted our area would be hit by the storm of the century with wind gusts exceeding 70 mph. Indeed, some coastal areas were hit pretty hard. There was even a tornado down in Oregon. Whoa! That’s just weird. But here in the South Sound area, we were really surprised and pleased when we clocked our top wind speed at 38 mph, which barely makes Galapagos wake up from her slumber in the slip. Whew! What a relief!

A tree in Tacoma waits for the wind.

A tree in Tacoma waits for the wind.

So this time, the science/art that is weather forecasting just plain old got it wrong for our area. If you are interested in why, here’s a local article that explains how mother nature always has a few tricks up her sleeve. Scattered around the world, groups of professional, knowledgeable weather forecasters couldn’t believe it, as they examined the radar images and worried that people wouldn’t believe them next time a big storm was coming. Tell you what: I will believe them and I hope you will, too. I’d rather be over prepared than caught by surprise.  It just goes to show how difficult it is to predict the great mother’s wrath. It’s good to put that into perspective before one heads out to sea. Think about it. These are experts. The rest of us are not. If they get it wrong, we certainly can, too. Just saying. I think we’ll just stay on the safe side by giving possible storms a wide berth as much as possible.

Since I have faith in science, I thought I would engage in a little experiment on board Galapagos, just for fun and because I am easily amused. Recently Practical Sailor magazine had an article comparing brands of toilet paper in terms of their ‘dissolvability’ and, thus, how hard they are on a boat’s holding tank system and how likely they are to cause a pollution problem if pumped overboard. They did a test with several different brands, both regular brands and ‘marine’ brands and reported on how fast they dissolved in water. I thought it was a pretty interesting test. It got me thinking. What was all our toilet paper doing in our holding tank? Was it decomposing? Was it sitting there in a large mountain of yuck? How could I find out without getting into a disgusting project? Literally. And what difference does that make, anyhow?

Well, I’ll tell you, because if you don’t live on a boat, you’ve probably not given this much thought. The United States has laws about pumping your sewage overboard, and we follow those laws. But other countries do not have the pumpout facilities that we have here. In some places, people just pump their sewage overboard right there in the same bay you are anchored in. Kind of gross, but there it is.

Because I’ve been raised here in our country where we have things like waste water treatment and where I am educated enough to care about the environment, I’d kind of like to be able to discharge our sewage in the highest and best way possible, given the fact that I’m not going to spring for a big waste water treatment facility on our boat.  If I’m snorkeling somewhere, it’s really going to gross me out to see large clumps of human waste and toilet paper floating by. So I don’t want to submit others to that, either. Galapagos has a macerator pump that grinds everything up before discharging, but what if we could use science to make the discharge that much less ‘papery’ in the first place? And also what if we could break solids down before dumping them overboard, even at sea? That would be a win for everyone.

When I refurbish ours it will look like this.

When I refurbish ours it will look like this. I like to think of this as industrial art.

Some people solve the toilet paper problem by never putting toilet paper down their marine heads. That works pretty well in the United States, and especially in the marina where you can take your trash out regularly. But we won’t be able to take our trash out regularly when we are cruising.  Plus, we have those lovely heads that rarely get clogged. We have the Crittendon Marine Skipper II heads. Those who have them love them. We’ve literally had people tell us how envious they are of our toilets. (That’s right. That’s what happens when you live on a boat. People look at what kind of toilet you have.) With these babies, we don’t really worry about clogs too much. We don’t mind throwing our tp out with the trash here in the marina, but I’m kind of loathe to keep bags of used tp somewhere in my boat for weeks at a time. Call me a princess.

So we don’t worry about clogs, but we do worry about solids building up in our holding tank and then sitting there forever rather than getting pumped out. Those solids are usually in the form of un-decomposed toilet paper. And that’s the long story about why this Practical Sailor article caught my eye. Unfortunately, they did not test our brand of toilet paper: Kirkland from Costco.  We have also been using Zaal Noflex Digestor in our tank and I wanted to know if that actually worked to help break down the paper. So I set up a small laboratory in the galley down at Galapagos and commenced to testing. Science!

The goal: to determine how long it would take for plain toilet paper to decompose in plain water, plain water plus Noflex Digestor, and salt water plus Noflex Disgestor. I did not test using plain salt water because I forgot. Maybe another time when I’m bored.

The set up: Three flasks, or, in this case, cups and glasses, each with one square of double ply Kirkland brand toilet paper.

From the left, salt water/digester, fresh water/digester, fresh water alone.

From the left, salt water/digestor, fresh water/digestor, fresh water alone.

Flask number 1: plain water and tp
Flask number 2: plain water, tp , and a pinch of this digestor
Flask number 3: salt water, tp, and a pinch of the digestor

Each solution with paper was given a couple of stirs with a fork. Then we waited.

Nine hours later, I checked to see how things were going. The results were already startling. The tissue in the plain water had not broken down at all. It came up on the fork in one giant piece. Imagine watching cool fish underwater when this baby, used, comes floating by. EWWWWW.

Intact piece of toilet paper.

Intact piece of toilet paper after 9 hours in plain water.

The tissue in the plain water with the pinch of digestor was beginning to break down significantly, coming up on the fork in small clumps. The tissue in the salt water/digestor mixture was a little behind but was starting to break down. We waited overnight.

Plain water with a pinch of the digester. Significantly deteriorated after 9 hours.

Plain water with a pinch of the digestor. Significantly deteriorated after 9 hours.

About 24 hours after I began the experiment, the plain water/paper was still intact, but seemed smaller, like it had less mass, even though it was not disintegrating into pieces. Still, when I swished it around, it held together. The plain water/digestor/paper mixture showed that the paper was dissolving and that there were only small pieces left floating at the bottom of the container. It was going fast. The salt water mixture was still behind, but was also decomposing the paper. It was just taking longer. (I poured each one into a colorful container to make photographing easier.)

Plain water alone.

Plain water alone after 24 hours.


Plain water with digestor after 24 hours.

Closeup of the salt water with digestor.

Closeup of the salt water with digestor.after 24 hours.

I gave them all a stir to simulate agitation due to boat movement. Then decided that I would add another pinch of the digester to see what happened. Unfortunately, I got excited about adding the product and added it to all three containers. Oops! There went my plain water control.

Within 5 minutes the paper that was previously in the plain water and looked like it was still a solid sheet was beginning to disintegrate. This leads me to believe that it was beginning to decompose on its own and that I just had not waited long enough. Anxious to test this hypothesis, I began another batch with just plain water and 1 sheet of toilet paper. I want to see how long I would have to wait for this paper to decompose without adding any of the digester.

I’ll report back on how that part of the experiment goes, but the results of this test were already very clear. While we are at the dock, we can use a fresh water flush and add the Zaal Noflex Digestor regularly and we’re going to be fine when it comes to pumping out. The directions on the container say to add a bit every day or so, more or less, depending on whether you have buildup in your tank already. This stuff works, and we can keep buying our usual brand of toilet paper and skip the expensive marine stuff. When we are traveling we can continue to use the Zaal, and we will go to a salt water flush to save our fresh water. I’m betting the constant motion of the boat will keep things agitated enough to encourage decomposition. I’ll be putting in a good supply of Zaal Noflex Disgestor before we go.

One caveat is that we use plenty of water to flush, and we make sure to clear the pipe every time. The extra liquid is going to help the digestor get to everything in the tank, even if we have to pump out a little more often. It’s worth it. Oh, and by the way, there is no ‘head’ smell when we use this. Nada. None. That, alone, makes this product a ‘win’.