To add or not to add? This is one of the big questions for anyone, like us, who lives in a home with a septic tank.
For many of the eighteen years we’ve lived in rural Oregon, we’ve dutifully added enzymes to aid the tank’s digestion of our waste. Whenever we’ve had our tank pumped or a line unclogged, the workmen have pushed an enzymatic additive, saying it’ll help keep our septic system healthy.
But is this true? After some Google research today, my conclusion is…No.
Save your money and let nature do its thing. Mag Ruffman, the Tool Girl, says:
There are 1200 products on the market for use in septic tanks; some contain biological agents like bacteria, some contain enzymes, and others use chemicals as their active ingredients. Extravagant claims have been made for many of them. The truth is, there are more helpful bacteria in a single poo than you’ll find in most biological septic preparations. Enzymes have not been proven effective in controlled tests.
What I found was that those selling septic enzymes are enthusiastic about them. But people without a financial ax to grind mostly said they aren’t necessary, and can even be harmful (see here, here, here, and here).
The state of Washington has banned septic tank additives. Here’s an excerpt from a Department of Health publication:
In 1993, the Washington State Legislature found that ” most additives do not have a positive effect on the operation of on-site systems, and can contaminate groundwater aquifers, render septic drainfields dysfunctional, and result in costly repairs to homeowners. It is therefore the intent of the legislature to ban the use, sale, and distribution of additives within the state unless an additive has been specifically approved by the Department of Health.”
In 1994, the legislature added, “Chemical additives do, and other types may, contribute to septic system failure and groundwater contamination. In order to determine which ingredients of non-chemically based additive products have adverse effects on public health or the environment, it is necessary to submit such products to a review procedure.”
Approved products merely are certified to not be harmful. There’s no evidence they’re effective. Apparently septic tank additives might be useful only in some special circumstances:
The beneficial effects of biological additives on the septic system are still being debated, but two benefits may ultimately be identified. Based on available literature, enzymatic products might have the ability to reduce the amount of oil and grease in the septic tank. Second, under septic tank bacterial “die-off” conditions, slight reductions in the amount of effluent solids have been achieved by using additives.
On the downside, this article says that additives can clog your drain field by pushing solids up to the surface of the tank and then out into the soil.
Bottom line: almost always, septic systems don’t need additional enzymes or other additives. We’re going to stop using them.
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Over the years I think you have thrown your money away!
Adding chemicals and having tanks emptied every year is simply a confidence trick perpetrated by the industry.
Provided the tank fitted matches the size of family and that the system is used as intended a tank will go for years without problem,
certainly it will not need to be emptied on a regular basis.
The size is based on a worst use scenario, usually, if used correctly, they will not need to be emptied for years.
Take a look at history to see what other people have done in the past.
I’ve put some notes together that you may find interesting, these may help you to avoid future problems.
Like, is my tank full? A tank is always full! Of water, with a crust on top and usually a very small amount of solids.
The main thing to note is that a septic tank used as intended, will probably never need to be emptied. Nor require any maintenance.
The septic tank was invented by a Frenchman John Louis Mauras who in the 1860’s built the first septic tank/ brick pond.
On opening it after 12 years he was surprised to find it almost empty. John patented his invention on the 2/9/1881.
The first real septic tank was designed by Donald Cameron and built in Exeter, England in 1895 it was 64 feet long 18 feet wide and between 7 and 10 feet deep. It had a surface area of 3600 square feet and served 30 houses and a large reformatory. It could process 90,000 gallons a day.
After 13 months it was opened and found to be almost clean, apart from some gravel washed in by the rain.
Septic tanks work by anaerobic process of de -composition turning our toilet into mainly methane, hydrogen sulphides, ammonia and carbon dioxide in an oxygen free process.
Our toilet is 70% water so the solids are very little and after process they more or less disappear.(see below)
The system works by separation, the oils and buoyant things like grease float to the top, under this is a layer of water based liquids with a suspension of tiny solids that gradually fall to the bottom, to de-compose. At the bottom the compact sludge.
The key thing is the quantity of oil and grease/lard that you put down the kitchen sink.
Over time the build up of oil and grease/lard in the top of the tank will result in neat oil flowing into the drain field and spoiling it.
All oils and grease/lard should be collected and placed in the dustbin.
Things like frying pans and other oily/greasy kitchen things should be wiped dry with paper towels prior to washing and the towels dropped in the waste bin.
The same treatment for plates etc; sprinkled with salt. (Sodium chloride)
The use of dishwashers and water softeners should be avoided in hard water areas as these use salt (Sodium chloride) as water softeners.
Salt is an antiseptic and over time it builds up in the drain field and stops it working. It blocks the soil pores and slows or even stops the flow of water from the drain field.
(You can buy a chemical treatment, that restores the field to use for a time. Usually needs treating once a year.)
RV Toilet Chemicals.
If you are still using Thetford Aqua-Kem Blue This is a strong poison and antiseptic! Do not empty your toilet tank into your septic tank on arriving home, Aqua-Kem contains formaldehyde which is an antiseptic, more powerful than Sodium. It will kill the process in your septic tank, that may not restart and will required emptying.
Thetford Aqua-Kem-Green is OK.
Restaurants, hotels and similar who do a lot of cooking find it helpful to fit a grease/oil trap between the sink and tank.
If you look on the net you will find that there are many people who have not emptied their septic tanks in 30 years and yes like mine fitted in 1985 they a still OK and going strong and trouble free, free flowing clear liquid and a nice crust on the top.
Some people recommend empty every year, this is trotted out regardless of the size of tank and drain field or the number of people using it. Or indeed if it is used or not!
Experience suggests that the longer the time the suspended solids have to settle and the larger the volume of free water/liquid the better the tank works. The best transit time seems to be between 36 and 48 hours and is best accomplished by a journey of around 8 feet.(Across the tank.)
One could also say that the timing of the days events and the order of process will have an effect. The smaller the transit space the quicker the fluids and suspended solids will pass through it into the drain field.
One should aim to let the drain field dry out over night. (8 hours of none use if possible.)
When to empty, in practice waiting until you have a minimum of 12 inches /30cms of clear water/liquid between the top of the sludge and the bottom of the outlet pipe seems to work.
However, keep in mind the build up of oil/grease/lard if your housekeeping is not up to standard.
If your tank is designed to serve twelve people and it is only used by two people, then emptying it every year or two is a nonsense.
There is a built in space for floating substances oil and grease, once this is exceeded oil will flow into your drain field.
It is a good idea to make a pole about 10 feet long with a plastic bottle on the end that can be passed down inside the tank to ascertain the remaining space on top of the sludge. Do this through the inlet pipe.
The sludge is quite firm and a plastic bottle small enough to go down a 4 inch pipe will do the trick.
You will feel the top of the sludge without problem.
The secret of longevity is : Control the things you put into the tank. Toilet paper is not a problem.
Never put alcohol products down the sink, alcohol is an antiseptic and will kill the process.
Only put into the tank things you would be willing to eat or drink. (except alcohol.)
Use other methods to dispose of other things.
Keep in mind that the process requires and generates its own heat, avoid letting cold rainwater get into the tank, expect the process to slow in the cold of winter and to flourish in the warmth of summer.
If you live in a cold part of the country consider covering the inspection covers with 5 inches of polystyrene to keep the cold out,
make sure the pipe to the tank, the tank and drain field are below the frost line.
It is good practice to limit the amount and volume of cold water entering the tank, as large volumes of water will wash the suspended solids through the system into the drain field and stop it from working.
Make sure the lids fit properly and that the area round them is designed to let water get away without forming a pond.
A trench or French drain installed above the septic tank and drain field, diverting the surface water away to one side is useful.
The tank will come to a halt when it is not used for a time and then start up again when brought back into use.
We have had a septic tank in St.Lucia for 18 years also. It only handles the bath water and toilet discharge. Because Mother always used yeast in her tank, that is what we have added down here. Does it work? Who knows. An old wives tale? Probably.
In the case of our kitchen sink, we have a leach line. This recently plugged up and I decided that I was pouring too much grease down the pipes, even if I followed it with soap and hot water. Draino does nothing. When the grease is congealed, all you can do is dig it up.
We are currently having septic problems due to rain in our area, ground is soaked so the tank isn’t draining like it should. How does one seal the lid to the tank so it doesn’t allow rain water to seep in?
Sorry for commenting on such an old thread, but I’m troubled when I see articles like this and the research that it came from because it’s too narrow minded (focused only on the typical anerobic conditions that the systems were originally designed for). I do agree that there are problems with additives (no labeling requirements, people not matching the product to the problem, market flooded with junk, etc) but there are several really good additives out there based on new research that shows how aerobic techniques can be applied to these old systems (e.g., CESS-FLO, Septic-Scrub, Septic Seep), and some good mechanical devices (e.g., Aero-Stream) that can really help in the vast majority of situations. I brought my system from total failure to functional just by using things that boost aerobic bacteria. In fact, I started a blog to help share my “journey” with others having similar problems. Use my URL link if interested.
very helpful in maintenance practice —— which is all that is required to continue successful utilization of an existing working system.
That has to be the most asinine comment made about septic systems in general. Bacteria and enzymes, not one or the other, they both need to be used anywhere from 3 to 6 weeks. It will support a healthy system. Going off a study conducted in the ’80’s and then published in the ’90’s has no validity. bacteria is what our systems run off, that was the design. “Letting nature take it’s course” is correct, except for the fact that all we do is kill healthy bacteria every day. Our soaps get stronger, every detergent is “anti” bacterial. Further more when they designed the septic system, they didn’t say “oh we should get a guy in a truck to pump it out from time to time’? It was designed to run on it’s own but of course we screwed that up by adding chemicals into our everyday lives. And Washington can not ban anything that is naturally occurring and harvested directly from the earth and that is a part of every system no matter what. So yes add additives just make sure its fortified with enzymes and keep your system running without trying to keep some politians “brother-in-law” in business pumping out your system unnecessarily. To say they clog systems is just a bold face lie. Bacteria is what in your system to begin with, man be responsible when you write, some people may actually believe you…..
The most important thing you can do to rejuvenate your septic tank and solve septic system problems is; stop putting enough non-biodegradable, non-settlable, tiny, poly fibers into it every year to carpet your living room. That’s exactly what you are doing right now unless you have a good +300 micron washing machine lint trap on your laundry drain.
I use 2lbs brown sugar 2 packets of yeast in a 5 gallons of water,let activate and pour in the drain or straight in the tank. I used store bought product which caused a crust that wasn’t there before.This is a new house and my first septic tank.It is big,5, 75 foot drain fields.I think it worked better when the kids were home.With just the two of us,I wonder if we are using enough water?PS my farm friends laugh when I tell them,I pumped my septic out.
A lot of household cleaners, and even some appliances can actually contribute to septic tank problems. Check out this blog entry I just read:
http://www.hycura.com/#!Five-Common-Septic-Tank-Problems/c135c/
I have been in the septic business for over 17 years. And for anybody to say that an additive is not needed because they looked it up on google is not very smart. Truth is. More times than not. It is needed. To many people use bleach and other chemicals that kill the bacteria that live in septic tanks. With this happening the solids can not break down properly. This causes blockages and other issues within your septic system. Please consult an actual septic specialist before listening to people that think they know what they are talking about because google told them so. Or you can listen to the and make a lot more money for people like me. But i would rather save you money than take your money.
I was told to use 2 cups of yeast and 2 cups of sugar and 5 gallons of warm water