"I stink, therefore I am," says my philosopher. He lives under my RV, and travels everywhere with me. He is a rather nondescript fellow, about six feet tall, four feet wide, and a thin six inches thick. He seems to prefer a dark suit, in fact, every time I lay eyes on him, he's laying about, clad in the black skin of plastic suited to folks of his kind. Although he is never invited inside, from time to time he does -- in an awful way -- make his presence known. He is a windy fellow, and many of my associates simply state, "He's full of it." And so he is, for my friend the dark philosopher is a black water holding tank.
As much as I try and force him to keep his ideas to himself, he does on occasion air his opinions. Usually my better half, she with the more sensitive of noses, is the first to complain. "You've got to do something about this!" she'll yelp, making a rapid exodus from our little room of rest. It is perhaps the torture stake of the male species, this job of being resident problem solver.
To keep my dark friend happy, I feed him a gruel of enzymes and bacteria, guaranteed to be "earth friendly," and to relieve my friend of unwanted odors. To be sure, when it doesn't work, I'm not sure who makes a bigger stink--my tank, or my wife.
For Them That Sits In cases of dueling nostrils, many are the causes of black water terror. In a recent instance, oxygen--or a lack thereof -- turned out to be the culprit. You may have read our treatises on holding tank brews. Some just try and kill the odor with perfumes. My personal favorites are the ones that use enzymes to break down solids, and friendly bacterial fellows that eat what's left over. No undigested solids, no stink.
All well and good, provided you keep the soup happy. Our bacterial brigade likes oxygen, and after sitting still in the same spot for several weeks, there wasn't enough "shakin' goin' on" to keep the oxygen distributed through the holding tank. Result -- the bacterial fellows were unhappy, leaving the job half done. Solution? Fill up the tank completely, then dump it. Now nearly fill the tank, add a half cup of baking soda, and let the whole thing percolate for a couple of days. Yes, you can still use the biffy with buffer. After two days, dump the tank, then reintroduce the holding tank bacteria.
One more suggestion for those who sit, and hence not agitate their tanks. Use more flush water than you might otherwise. Yes, it makes for more frequent black water dumping, but the increased liquid level will aid in flushing out what solids may have built up by dumping time.
"Water Don't Run Up Hill" No sooner than I had my own stench squelched, friends called in desperation. The smell from their black water system was so bad that they couldn't bear to stay in the RV. Now that's a heady thought. Before you can fix, you've got to di-ag-nose (heh heh) the problem. Since the odor was so pervasive throughout the house -- and not just in the throne room, it hardly seemed the odor was just wafting back up when the toilet was flushed. Still, this isn't a bad place to start looking: Does the toilet bowl "hold water," or does it dry out between flushes? If the toilet seal at the bottom of the bowl isn't tight enough to hold water in, it certainly won't keep the smell from running back up topside. No water seal? First try the old coat-hanger in the toilet seal trick. Shut off the water supply, step on the evacuation pedal, and using a coat hanger, carefully run the tip of the wire around in the flange that the bowl flapper seats in. Often times crud will accumulate in the seat, making a solid seal impossible. If that won't affect a cure, you may need to replace the toilet mechanism (or the terlit) to get a good seal.
In this instance, the toilet was new, and the bowl seal was solid. A trip up topside to investigate roof vents was revealing. It seems some RV builders like to bore BIG holes to put little pipes through. The 2" vent pipe was passing through a hole much larger -- and for the most part, nothing prevented the sewer gas from rolling down that wide gap between roof and vent pipe, making for a swell stink entry into the coach. Some non-sagging sealant caulked in between the vent pipe and the roof solved that issue.
Still there were a couple of other items we flushed out. The rig in question was more or less permanently "moored" in an RV park. The rig had been skirted, and dump valves extended to outside of the skirting. It became obvious that the company that modified the plumbing forgot the first rule of plumbing: "Water don't run uphill." (The second law, is "Don't lick your fingers.") While the dump valve was below the holding tank, the pipe ran uphill to get to the valve. A flashlight pointed down the toilet revealed an accumulation of solids -- possibly due in part to this uphill bottleneck. After we blasted out the holding tank with a cleaning wand, we admonished our friends to make sure their tank was nearly full before dumping.
Proboscis Problem Pointers To recap, what if your head is too heady? First, make sure your holding tank is happy. Don't use "home-brew" holding tank treatments. Formaldehyde containing treatments may be handy, but they kill healthy digesting bacteria and in some places cannot be lawfully dumped.
If you're not traveling and keeping the tank stirred up, use plenty of flush water and follow the directions on your holding tank treatment closely.
Make sure your toilet seal does seal. Clean or replace as needed.
Make sure your roof isn't open to venting unwelcome odors into the coach. And make sure the vents aren't clogged with bird's nests or other debris.
Don't dump your tank unless it's nearly full. You need a full "head" of pressure to flush them nasty solids away. Waiting until the tank is at least three-quarters full is a good rule of thumb.
Don't run the bathroom exhaust fan when flushing the pot. You may suck the smell right back up out of the tank and into your coach.
My philosopher friend urges that dogged determination may be required to track down and cure a smelly problem. At least that's what I translate--"When pesky pots pose proboscis problems, probably pointed poking will prevail." 'Nuf said.