Tank odors are caused when "bad" bacteria (anaerobic bacteria) inside your black and gray tanks emit hydrogen sulfide, that all-too-familiar methane smell. If you don't control the anaerobic bacteria inside your tank you're bound to have foul smelling, embarrassing odors. Luckily, with a solid understanding of what's happening inside your tanks and proper treatment you can eliminate these odors easily and affordably.
How anaerobic bacteria gets into your tank and how you can get rid of it.
Inside your stomach you’ll find loads of anaerobic bacteria. These bacteria help break down the food you eat and are a crucial part of the digestion process. When you go to the bathroom these anaerobic bacteria end up inside your black water tank. As they continue to do their job – break down and eliminate solid waste – they emit hydrogen sulfide. This is where your toilet smells are coming from.
So, the trick to eliminating tanks odors is getting rid of anaerobic bacteria. There are two ways to do this:
Killing Beneficial Bacteria
Caustic chemical treatments and many of the “natural” RV holding tank deodorizers, like mineral or formaldehyde treatments, try to achieve odor elimination by killing the naturally occurring anaerobic bacteria inside your tank. This has two HUGE problems. First, by killing the bacteria you are practically begging for a clog or backup inside your tank. Bacteria are exactly what you want in your tank to keep them liquified. You just want the right bacteria – more on that in a minute. Second, many of these products aren’t very good at fully eliminating the smells so they also come with very potent fragrances that can be very overwhelming (and some are full of dangerous chemicals as well!). When you treat your tanks with these products you’re opening yourself up to a clog, using dangerous chemicals, and to top it all off, you get an overly potent fragrance inside your RV that can be just as putrid as the tank odors you were trying to ward off. In other words, killing the anaerobic bacteria is a bad idea.
Force Beneficial Bacteria Out
By treating your tank with a good aerobic bacteria you force out those bad anaerobic bacteria and replace them with good aerobic bacteria. As we mentioned before, anaerobic bacteria thrive in oxygen-free environments and emit foul smelling hydrogen sulfide gas during the breakdown process. Aerobic bacteria, however, thrive in oxygen-rich environments (like inside your holding tanks) and they release only carbon dioxide and water as they break down waste – which leaves your tank contents liquified AND odor free.
The most all-around effective way to eliminate odors while maintaining good solid waste breakdown inside your tank (so you don’t get backups) is to replace the stinky anaerobic bacteria with aerobic bacteria. Treating your tanks with a good bacteria-based holding tank treatment that uses high concentrations of high-quality aerobic bacteria strains to force out the anaerobes is crucial.
Unfortunately, many of the bacteria products on shelves today don’t have high concentrations of high-quality bacteria strains. Many of them have low counts and inconsistent bacteria strains. This is mostly because either the manufacturers are trying to save on cost (high-quality bacteria are expensive!) or they don’t really know what they’re doing. There are numerous products on the market that are just private labeled junk and unfortunately the companies selling these product don’t even know that they’re providing a low quality bacteria product.
Using Unique RV Digest-It to effectively eliminate odors and digest waste.
RV Digest-It infuses a blend of naturally-occurring aerobic bacteria into your tank to replace the anaerobic bacteria and quench the foul odors. It does this by breaking down the solid waste inside your tank while giving off only water and carbon dioxide. Unique’s proprietary blend of safe, eco-friendly bacteria is much more concentrated than competitors’ brands and outperforms competitors’ products by breaking down waste faster, eliminating odors better, and leaving behind no residue in your tanks to clog lines, foul up sensors, or degrade seals.
Simply put, Unique spares no expense in creating the highest-quality bacteria blends with concentrations that far exceed competitors’ products. This means better waste break-down and stronger odor removal. And to top it all off, it’s less expensive per use than leading tank treatments!
Odors inside a holding tank are bound to happen on occasion, but if you are doing all the right things you shouldn't experience those odors inside your RV. When you smell odors inside your RV, it’s a good indicator that something isn't right and it's a smelly reminder to address some problems.
Here are some common reasons for why tank odors make their way into your RV, along with tips on how to eliminate them:
Not enough water in your toilet
Water is a natural barrier for sewage gases. In your home toilet you have a trap that always keeps water in the line, preventing sewer gas from seeping into your home. Not only does sewer gas smell terrible, but it is also dangerous and can be damaging to your health if you allow it to seep into your RV.
To ensure no tank odors seep into your RV, always keep a few inches of water in the toilet bowl whenever you are parked. Obviously, you will want to flush the water from your toilet before traveling so the water in the bowl doesn't splash out.
Not enough water is getting into your tanks
If there is not enough water inside your tanks, the waste could dry up, killing the naturally-occurring bacteria. Dead bacteria can’t digest waste, so the waste will not break down, and odors will occur. So flush your toilet often and generously.
Your vents might not be working correctly
Again, just like your home, your RV is equipped with a vent that allows the naturally-occurring sewer gases to escape out the top of your RV so the smells don't back up into your RV. If you are experiencing odors in your tank, there is a good chance that you need to look at your exhaust system.
Several things can cause your exhaust system to underperform. Outdoor temperatures or wind can force downward pressure on sewer gas, causing it to back up into your RV. Installing a vent cover, fan, or damper can help eliminate this problem. There are even turbines that will use the wind above your RV while you are moving or stationary to lift the sewer gases out and exhaust them into the air.
Because there are so many options available, try to "sniff out" (pun clearly intended!) the root of your problem to determine your best solution.
It’s hot out there!
It's important to understand that bacteria are living organisms and just like us, they tend to work less if they are hot. This becomes a problem as temperatures increase inside your tank.
To ensure the bacteria in your tank are performing at their peak, be sure to regulate the temperatures in your tank. The ideal temperature for properly-working holding tanks is roughly 45 degrees Fahrenheit to 85 degrees Fahrenheit. If you encounter extreme heat and believe your tanks might be exceeding 85 degrees you may need to pour some cold water or ice into the tank. (If you are in extremely cold areas bacteria activity is a concern, but so is freezing of the sewage, so explore your options for ensuring your holding tank is well-insulated. You may need to use a heater as well, depending on your situation.)
We could go on for hours about why bacteria are the best way to go when selecting your tank treatment - even with high temperature limitations - but we'll just assume that we’ve made our case well and that you agree with us. Because who likes dangerous chemicals and overbearing fragrances!? (If you’d like more information on the different types of treatments check out this page.) Don't worry, though! You can live odor-free, even in extremely hot temperatures, using a bacteria product if you follow some simple procedures when the heat rolls in!
If outside or tank temperatures exceed 85 degrees Fahrenheit, do the following to make sure tank odors remain at bay:
Our response for people dealing with foul odors in high heat is to use Tank Odor Eliminator. Tank Odor Eliminator is a salt/mineral blend that completely controls odors in the hottest temperatures. Stop putting up with odors and deal with your tank smells head on. Read our article about treating odors in high heat here.
Salt/Mineral treatments are not always the safest products. Please follow all safety instructions when using this product for the best results.
It is very important that you consider the solid waste in your tanks. So often, people only think about the odors in their tanks and neglect to ensure that the waste is being digested properly. Many of the popular "treatments" only eliminate odors or may even just mask them! They not only fail to digest waste, but they actually make the problem worse by adding heavy minerals to your system. These minerals coat your toilet bowl and lines, damage your tank sensors, and degrade the rubber seals that keep sewer gas from seeping out of your tank.
To ensure proper breakdown of solid waste, make sure your valve is closed unless you are dumping. Use RV Digest-It to digest difficult solids like grease, toilet paper, and human waste. Ensure enough water is the tank so waste never dries up or becomes thick. Do not allow any chemicals or anti-bacterial soaps in your tanks. And NEVER allow flushable wipes into your tanks.
So, now that we’ve given you the reasons why odors occur in your RV and tips on how to avoid them, here’s a recap: