RV Holding Tank Treatment Comparison Chart

Image grid of different types of products and how RV Digest-It Holding Tank Treatment fits into that world

Understanding The Different Types Of Treatments


Holding tank treatments come in four major variations

  • Chemical / Formaldehyde
  • Enzyme
  • Mineral / Salt
  • Bacteria
There are other types of treatments, but the overwhelming majority of the products available fall into one of these camps.


Chemical / Formaldehyde

Many years ago these were the only treatments you would find in your local RV parts store. These products were introduced primarily to “encapsulate” or mask odors using chemicals or formaldehyde. These products don’t normally do anything to breakdown waste and unfortunately are normally quite dangerous. Formaldehyde, for instance, is quite dangerous for your health and studies have shown it can actually cause cancer.

The other frustrating byproduct of chemical or formaldehyde RV treatments is that they typically include incredibly foul-smelling fragrances in their formulas to help mask the smell of poop in your tank. If you haven’t ever smelled these products, it’s hard to explain how strong the fragrances actually are! Many claim that they are worse smelling than the actual toilet waste! Because these products typically do nothing to break down waste, you’re essentially asking for backups and clogs that can send poop and pee back into your motorhome. And to top it off, you’ll get to smell the over-powering smells of cancer, er, fragrance! Needless to say, you should avoid these types of products at all costs.

Oh, and here’s the best part! Most of the major RV manufacturers install toilets by major toilet manufacturers who make these types of horrible chemical / formaldehyde products and tell you in their instruction manuals that you need to use these nasty products to ensure your toilets work correctly! They probably even gave you a free sample of this junk when you bought your RV! Throw it away and start using a better working, healthier, safer alternative!



Enzyme treatments are a great solution for quickly breaking down waste but unfortunately do nothing to eliminate odors – unless they’re packed full with odor-masking fragrances. Many people confuse enzymes and bacteria and it’s important to understand the differences.

Enzymes are non-living proteins that literally break down waste. They take big chunks of your toilet waste, like toilet paper and feces, and break it down into smaller particles. And typically the work fast.

Besides doing next to nothing to eliminate odors, enzymes have limitations. For one, unlike bacteria, they don’t grow in size. Simply put, if you pour 1 million enzymes into your black water tank you will still have 1 million enzymes in 20 years, whereas bacteria will continuously grow in count as they populate or “colonize” inside your tank.

Another problem with enzymes is that they can be potentially dangerous to people who are allergic to enzymes so it’s important that you don’t inhale any products that vaporize (puff into the air) and contain enzymes. This can often be the case for powder treatments that contain extra-cellular enzymes.

Finally, though enzymes are very fast working and can perform well in extreme temps (very high or low) they don’t necessarily eliminate waste. They simply make it smaller. Only bacteria have the ability to completely eliminate (biodegrade) waste until it is completely gone.


Mineral / Salt

One of the more popular methods of odor reduction today is using minerals and salts to chemically neutralize odors. On the one hand these are great because they don’t mask smells with heavy fragrances, however they also do nothing to break down the waste – so get prepared for tank clogs and backups.

Another VERY important thing to note about these mineral / salt products is that they are very often dangerous – even though you would never know it by looking at their labels. Many of the top products contain Zinc Sulfate Monohydrate (or variations of zinc) and these are often labeled as “Organic” simply because they mine the salt or mineral from the earth.

We hate to be the bearer of bad news and point this out, but lots of dangerous things are mined from or found naturally occurring on the earth – like arsenic, asbestos, or formaldehyde. Just because something is found in nature doesn’t make it “Organic” or for that matter, safe! To be labeled as “Organic” a product must go through strenuous testing and validation  and to my knowledge, none of the waste water treatments that claim they are “Organic” have ever gone through this testing.

Being blunt –  it is very frustrating that products labeled as “Organic” are introducing dangerous ingredients into the confined spaces of your RV. Many of you touch these products with your hands or inadvertently inhale them on a regular basis never realizing how dangerous they are to you, the environment, and marine life because they have green washed  their products by claiming to be “Organic”. User beware! 

Full Disclosure:

Unique Tank Odor Eliminator contains Zinc Sulfate Monohydrate (as well as waste-digesting bacteria) and it requires safety precautions be taken when using.

You may ask (and rightfully so!), why would Unique make a product that isn’t safe when you’ve been known as THE brand of safe products for over two decades? It’s a good question and one that prevented us from making Tank Odor Eliminator for many years.

Frankly, customers kept asking for a product that would eliminate odor and break down waste in high temperatures and in low-water applications, like dry camping, and bacteria/enzyme cleaners like Unique RV Digest-It have very real limitations in those situations.

We also knew that there were other products on the market using similar odor-reducing ingredients that routinely marketed themselves as safe and “Organic” when they really aren’t.

So, we set out to make a version that was self-contained in a drop-in pod so users wouldn’t be forced to inhale the product or touch it like users routinely do with other competitor products that use scoops for their dangerous powder.

The honest truth: If you have strong beliefs in using only safe products with the highest concern for the environment, then RV Digest-It is exactly the product you’re looking for. If you are routinely in situations (like high heat or dry camping) where odors are making your RV experience unbearable and unenjoyable, then you may be willing to overlook some of your green / health concerns and use Tank Odor Eliminator. The choice is yours and we will never try to make erroneously claims of this product being “Organic”. We want you to be informed of the products you’re choosing to use and we intend to be completely transparent and honest in these matters.



We've saved the best for last! Bacteria!

Now before you say to yourself, “Ew! Did they just say bacteria?! I’ve spent my whole life pouring hand sanitizer on everything to make sure there are NO bacteria in my life!” please hear me out! You’ll be glad you did!

Bacteria have really gotten a bad rap for the last hundred-or-so years, but actually, bacteria are incredible, little, natural cleaners! (How do you think food and trash biodegrades?)

Every day scientists discover new ways that bacteria greatly benefit our lives. Heck, we even take probiotics, eat yogurt, and drink bacteria (Kombucha) to make sure our stomachs remain full of healthy bacteria.

Truth be told – bacteria are one of the most under-appreciated organisms on earth. Without them we would probably couldn’t survive. Also, truth be told, there are some that are dangerous.

Luckily for you, the bacteria that are generally found in tank treatments are “non-pathogenic” bacteria – at least they are in RV Digest-It! That means they’re TOTALLY safe and healthy! Just like the probiotic you take every morning.


So, why are bacteria so great for holding tanks?

We're glad you asked!

Bacteria are a natural waste digester and odor eliminator. Bacteria are living organisms (just like you and me!) and they require two things to thrive, food and water. Both of these are found in your holding tanks as they feast on the items that you and I would think are absolutely disgusting.

Here's how it works:

When you add a bacteria product to your holding tank the bacteria began to feast on the waste in your tank and eventually liquefy the contents of your holding tank – including, paper, feces, grease, and other solids. This ensures you never get tank clogs or backups. One problem down!

The other thing high quality bacteria products do is they replace the naturally occurring anaerobic bacteria with aerobic bacteria. What does this mean? Odor elimination! As anaerobic bacteria from your stomach break down waste they let off hydrogen sulfide gas (that nasty methane smell you get in your toilet tanks and when you pass gas) – these smell makers are forced out by aerobic bacteria that let off carbon dioxide and water as they break down waste. This means complete odor elimination and no masking. And it’s done by completely safe, natural occurring bacteria! It’s a beautiful thing, isn’t it?

Remember how we mentioned at the beginning of this post that it was crucial to do both – eliminate odors and digest waste? Well, bacteria is the only solution that will do both.

Key Take Away Time! Bacteria are the only treatment option that do both, waste digestion and odor elimination. And they are the only option that are completely safe and natural! What more are you looking for?!

Something of importance to note: bacteria create enzymes. So, if you are using a bacteria product you are also getting an enzyme product! Bacteria’s only goal in life is to eat waste but unfortunately, they have very small mouths so they need to break down the waste into smaller, bite sized pieces before they can eat and digest the waste. To do this they create enzymes that take the big pieces and break them down into smaller pieces.

Another incredible part of bacteria is that they multiply and grow as they “colonize” the inside of your holding tanks. That means that as they digest the waste they keep growing in number and each one of them is producing more and more enzymes. So, if you start with 1 million bacteria, it’s only a matter of time before you have billions of bacteria and billions of enzymes.


Quality Matters!

The quality of the bacteria is incredibly important. You need to have high quality bacteria, in the right strains, with the correct formulations to work optimally. Many bacteria products available today consist of cheap, watered down formulas with completely wrong bacteria strains – so don’t simply assume that just because a product contains bacteria that it’s going to work! Luckily for you, RV Digest-It contains billion of the highest quality, best formulated strains of bacteria in each and every treatment.