Holding or septic tanks?

When an RV Holding Tank isn’t a Septic Tank

We’ve heard RVers call their tanks both things. We’ve gone over what an RV holding tank is RV Basics: What are RV holding tanks? before, but let’s have a quick review: Your RV has at least three types of tanks:

• Fresh water holding tank, which holds, as you guessed it, fresh, potable water. Sanitizing is key to your health with this tank, BTW.
• Black waste holding tank, sometimes referred to as a septic waste tank. This is where stuff from your toilet ends up.
• Gray water or waste holding tank, where anything going down sinks, showers, or tubs is routed to.

Despite what we might commonly (and mistakenly) say, your three tanks are holding tanks, not septic tanks (especially the black and gray, of course). They are designed — as the names imply — to hold things, not a place to compost or digest them up, as in a septic tank.

But everyone calls them a septic tank

We know. From RV manufacturers to RV sales people to RV repair shops and even owners, the black (especially) and gray tanks are commonly called septic tanks. But a smart RV practice is to forget this concept of septic tanks and think about them as a place where waste is only temporarily held, untouched and undigested.

What about RV tank additives?

Those chemicals, enzymes, and other biological agents you are adding to your holding tanks are intended (by and large) to do one thing: to breakdown and digest the waste in your tanks, converting it from a solid into a liquid.

The theory is that a liquid must be better than a solid, right? Wrong.

By adding those RV tank additives intended to break down solid waste, you are simply creating a super-thick, super-concentrated slurry of waste. You’ve converted a few solids floating in a great deal of thinner water into a mass of thick, pancake batter-like paste.

That’s the stuff coating your sensors and internal surfaces of your holding tanks, making it difficult if not impossible to get them truly empty. It also reduces the overall capacity of your holding tanks as now that thick slurry is coating every surface. Finally, that thick, sticky mess is causing odors and allowing them to linger longer as they refuse to be flushed out.

Still not convinced?

Your holding tanks are basically big plastic boxes with an outlet hole on the bottom of one side (or on the very bottom). Think about this: What would emptier faster, more completely, and without fewer hassles (like stuff left behind):

• A plastic box full of mostly water with a few solids (waste and TP) floating around intact around it, or
• That same plastic box full of the same amount of pancake batter?

In conclusion

So your holding tanks are just that — tanks that simply hold water and intact waste until it is time to empty them. They ARE NOT septic tanks. And adding an RV tank solution to them that breaks down the waste inside into a thicker, stickier slop is just plain dumb thinking.

How do you get your holding tanks clean after years of treating them like a septic system? Simple. Just call Kleen Tank and we’ll come out to you, assess the situation, and give your holding tanks a high-pressure, water jet cleaning. With thousands of tanks cleaned over seven years, we’re the right choice to get you back on track. Make an appointment today!

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