The Very Popular “Single Tank” Aeration Systems for Iron and Hydrogen Sulfide Have Issues

A particular style of iron/manganese/hydrogen sulfide filter that has become very popular in recent years combines aeration in the same treatment tank with the filter media. These are sold under a variety of names, like AIO, “iron breaker,” and “iron ox.”  (We call them “single tank aerators.”)  It is understandable that they are popular.  They are effective removers of reasonable amounts of iron, manganese, and hydrogen sulfide, they cost less than most alternative methods, they save space, and they are relatively easy to install.

How They Work

Single tank aerators are built like a standard backwashing filter with iron/sulfide media like Filox, Birm, Katalox, or Catalytic Carbon in a “mineral tank” with a control valve on top to backwash the media. They differ from standard filters, however, in that the control valve is a water softener valve that has been modified to draw in air instead of a brine solution. During regeneration, the control valve draws in and stores air in the filter tank. During the service run, this compressed air is used to speed up precipitation of the targeted contaminants. Since air is taken in only during regeneration, the regeneration process has to happen often. In most cases, a daily regeneration is required for residential treatment.

In air-induction units, air is drawn in through the screen-protected port during the daily regeneration cycle.

Issues To Consider

There are a couple of issues that should be kept in mind if you’re considering getting a single tank aeration/filtration unit. One is water usage. Single tank units have to regenerate every night, and they use more water per regeneration than conventional non-aerating filters. The table below looks at water usage for a typical 10″ X 54″ single tank aeration iron filter as compared with a non-aerating conventional iron filter of the same size.  The chart assumes that the iron level is moderate and the iron filter can be regenerated every third day. The aerating filter must be regenerated every night to maintain its air charge.

Water Usage of a Conventional Iron Filter vs. an Air Draw Filter

Stated differently, while a conventional iron filter may use 140 gallons of water per week, an air-induction filter of the same size will use about 665 gallons per week. This is water that is drawn from the well and also waste water that has to be disposed of.

Keep in mind, of course, that the aerating system can be much more effective than the conventional filter working without an oxidizing agent. Air provides pre-treatment that could also be done with oxidizers like chlorine, hydrogen peroxide, potassium permanganate, or ozone–all of which come with their own problems and disadvantages. Keep in mind, too, that there are other forms of aeration. The old venturi or “micronizer” systems use no water at all, and the free-standing compressor-p0wered aeration systems (AerMax, for example), cost more initially but are more effective and use only about 2 per cent as much water as the AIO units. (A  Pure Water Occasional back issue has a concise explanation of how all three aeration systems work.)

Another issue to be considered is upkeep. Filter control valves running on clean city water usually go years without internal parts failures. Not so with well water filters that have to deal with contaminants like iron and high sediment levels. Filter control valves have inner seals that degrade when exposed to harsh water conditions.  Such degradation is regarded as normal wear and tear, and well owners should expect to do fairly frequent maintenance on inner control valve parts like pistons and seals and spacers. While this is true of all iron filters, single tank aeration units are much more prone than standard units to experiencing inner gasket failures.  This is probably due in part to frequency of regeneration but it is more specifically because the 40-minute daily air draw cycle dries out and corrodes sensitive inner parts and leads to early failure.

Single tank aerators offer a quick and relatively inexpensive solution to well water problems, but buyers should be aware that they have some drawbacks.

Three thousand litres of water – that is the amount needed to produce the food each British person eats every day. This is according to a new study into the “water footprint” of diets in Western Europe, conducted by the European Commission and published in Nature Sustainability.

The term “carbon footprint”, which accounts for all the emissions of CO₂ associated with the manufacture or production of an item, has become commonplace in recent years. Similarly, the “water footprint” of food can be calculated using information on the amount of water required during cultivation and processing.

The authors of this new study, led by EC scientist Davy Vanham, first gathered existing data on the water footprint of various foods and drinks. They then combined this with census information for regions within the UK, France and Germany, and knowledge of local eating habits, to calculate how much water is used to feed people in each region and how that could be reduced. Considering the record-breaking heatwave and drought across Europe in summer 2018, their insight may have arrived just in time.

Of the three countries studied, the UK has the smallest average water footprint at 2,757 litres per person per day, in Germany the average is 2,929 and in France it’s 3,861 (for reference, people in the US use more than 9,000 litres per day). One of the standout reasons for the difference between these countries is that the French drink more wine, compared to the Germans and the British who prefer beer, which has a smaller water footprint.

Another feature of this study is the focus on smaller regions which reveals large differences within these countries. A common theme is that rural areas have higher water footprints than cities, mainly due to differences in diet. People in London, for example, eat less red meat than other regions. This is why the UK’s highest footprints (still less than France’s smallest footprint) are found in the south-west, North Yorkshire and Lincolnshire.

In Germany and France this trend manifests as a distinct north-south divide, with the French wine growing regions in the south-west using up to 5,000 litres per person per day. According to the study, another cause of differences within each country is the make up of regional populations. In London, the amount of wine consumed is closely related to the level of education of residents. In other words, water footprint increases with education.

But what does all this mean? Well, 3,000 litres a day adds up to more than a million litres per year — or enough water to fill your local swimming pool three times over. More importantly, a higher water footprint is associated with an unhealthy diet, largely due to meat requiring a lot more water than vegetables or fruit. In all three countries, people “eat too much sugar, oils and fats, (red) meat as well as milk and cheese combined,” write Vanham and colleagues, and in France and Germany “people do not eat enough fruit and vegetables.”

Eating less meat through adopting a “healthy meat” diet could reduce water footprint by up to 35%, the authors say. An even greater saving can be made if meat is replaced by fish, lowering water footprint by 55%, but interestingly moving completely to a vegetarian diet makes around the same savings. Making such changes will not only save water, but will have the additional benefit of improving diet in countries where more than a third of people are overweight and around a quarter obese.

Convincing people to make such a change to their eating habits will not be simple. A number of suggestions are put forward in the study, including punitive measures for “unhealthy” foods, such as a sugar tax. However, such approaches are controversial, with considerable evidence suggesting that they are harmful to low income families. A more subtle approach would be to change the layout of supermarkets, “nudging” shoppers towards more healthy purchases.

Finally, the authors acknowledge that education of the population in dietary matters will be key. But, as their own analysis shows, more education is associated with higher wine consumption, which increases the water footprint.

Ben Keane is a Postdoctoral Researcher, Soil and Plant Science, at the University of Sheffield.

This article is republished from The Conversation.

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Nitrates in Water: The Basics

The primary sources of nitrates in water are human sewage, livestock manure, and fertilizers. Areas with a high density of septic tanks and animal agriculture in close proximity to the drinking water source are most vulnerable to contamination by nitrates. Research has shown an increase in nitrates in water as both agriculture and population grows. While nitrates used to be a “well water” problem, many urban water suppliers  now having to work to keep nitrate levels down. (See Nitrate Levels in Drinking Water Are on the Rise.)

The foremost health hazard associated with excessive levels of nitrates in water is blue baby syndrome, a condition that affects the blood usually in infants 6 months old or younger. Young infants’ digestive systems convert nitrates to nitrites and can be fatal.

Nitrates and nitrites are very soluble and cannot be precipitated from water. They are not removed by conventional filtration.  This means they have to be treated with a chemical or biological process. The best residential treatments for nitrate contamination are reverse osmosis, distillation, and anion exchange. Reverse osmosis is normally the product of choice for residential applications. Anion exchange can also be effective but it is important to have a water analysis to show other contaminants. Anion treatment is less effective in water with high TDS, high hardness, and high sulfates.

EPA maximum contaminant levels (MCLs) are 10 mg/L for nitrate and 1 mg/L for Nitrite.

Vinyl Chloride

Vinyl chloride is not found in nature. It is a man-made cancer causer that gets into water supplies mainly as a result of manufacturing emissions and spills. It serves as a raw material to produce polyvinyl chloride (PVC) polymers (plastics). PVC is used to manufacture many industrial and consumer products: water and sewer pipe, wire insulation, floor and wall coverings, toys, medical devices, food packaging, etc.

Vinyl chloride is a known carcinogen. It is a danger especially to workers in manufacturing plants where it is used. As a water contaminant, the greatest danger is from contaminated wells.  It seeps into wells as a result of manufacturing leakage and spills.

Removal of vinyl chloride is accomplished best by filtration with granular activated carbon and by reverse osmosis units. Some distillers remove vinyl chloride.

Go here for more information.

A Filter Control Valve that Costs Less and Does Not Need Electricity

Fleck’s Simple 2510 Manual Control.  No Electricity Required. It Isn’t Sexy, But It’s Very Functional.

Fleck 2510 Manual.  This is the most basic of filter valves, yet in many situations it can be the best.  In spite of the low price, it’s a tough and durable piece of equipment.  The 2510 Manual is a  non-electric control that requires manual backwash and rinse.  It is, therefore, not practical if backwashing needs to be performed daily (as with many iron filters, for example), but for a clean city water application where chlorine removal is the main purpose, a monthly backwash is often sufficient and performing it can be a 15-minute task.  The valve operates with a simple selection lever and has only three choices: Service (means the filter is in service, providing water for the home), backwash, and rinse.  Performing the backwash and rinse is like shifting gears in an car: pull the lever to backwash and let it run for five to ten minutes, pull it down to rinse for a couple of minutes, then return it to service.

Simple lever-controlled programming includes Service, Backwash, and Rapid Rinse positions. No electricity needed.

The 2510 Manual Control unit has exactly the same capacity as the larger-format, fully automatic 2510 timer control, but it costs approximately $150 less and requires no electrical connection.

Suggested uses:

City water chlorine or chloramine filters that require only infrequent backwashing.

Remote installations like seasonal cabins where an electrical connection is not available.

“Off the grid” installations where saving electricity is high priority.

Installations where a permanent drain connection is not convenient. (The filter must have a drain for backwash and rinse water, but it can be hooked to a garden hose and used for lawn or garden irrigation. The filter’s drain can be easily fitted with a garden hose connection.)

Any intermittent-use application where it’s easier to regenerate the filter manually than to continually reprogram an electric control valve.

Prices they are a-changin’

When all the political smoke clears, the truth about “tariffs” is that they amount to a tax increase that isn’t called a tax increase.

And it isn’t the Chinese or the Mexicans or the Canadians who pay the tax. It’s American consumers.

For those who buy water treatment equipment, taxes are going up sharply. One of our vendors just notified us that all products from one major American supplier are going up 4 to 8 percent because of tariffs. Our main parts vendor has just notified us that the prices of filter media and softener resin, filter tanks, and control valves are going to increase sharply. That means prices of finished filters and softeners will rise considerably.

Prices tend to spiral. When a tax on Chinese carbon forces up the price, this allows domestic carbon makers some room to raise their prices and still remain competitive. Foreign-made and American-made both go up. And once prices go up, they hardly every come back down, tariff or no tariff.

In a nutshell: because of the tax increase, we expect that our water softeners, tank-style and cartridge-style filters, filter media and parts in general will be selling for about 10% more.  Very soon.

Chloride

Chloride, one of the most prevalent anions found in water, combines most commonly with the cations sodium, calcium, and magnesium.

Chloride levels in most waters range from 10 to 100 mg/l, and sea water contains over 30,000 mg/l chloride in combination with sodium, as NaCl.

Chloride is an essential electrolyte that helps to maintain pH, transmit nerve impulses and regulate cellular fluids.

Chloride in water is more a plumbing issue than a health issue.

Chloride, when concentrated, can cause corrosion of metal piping, so when treating water high in chloride plastic is usually preferred to stainless steel for reverse osmosis membrane housings. Iron is leached into water from metal pipes when high levels of chloride are present. Chloride is the main cause of pitting of stainless steel. Chloride combines with hydrogen to produce hydrochloric acid.

The suggested MCL for chloride is 250 ppm. Above this level water often has an unpleasant salty taste.

Reverse osmosis removes around 95% of chloride, and electrodialysis and distillation are also effective. In industrial settings, strong base anion exchangers can be used.

In practical terms for most residential users, in city water chloride is not a problem.  For well owners with high chlorides, undersink reverse osmosis takes care of drinking water.  If water is so high in chlorides that it is unusable for irrigation, whole house reverse osmosis is an option.

The World’s Most Polluted River

Environmental Regulation Matters

The Citarum is the longest and largest river in West Java, Indonesia. It is the third longest river in Java and has an important role in the life of the people of West Java, as it supports agriculture, water supply, fishery, industry, sewerage, and electricity. No one argues that it is perhaps the most polluted river in the world.

Despite the fact that the Citarum River has been named the world’s most polluted river by the World Bank, around 28 million people in Indonesia depend on it for irrigation and electricity — as well as nearly 80 percent of the capital city’s water supply.

It is estimated that more than 20,000 tons of waste and 340,000 tons of wastewater are disposed of directly into the waterways of the third-biggest river in Java every day from thousands of textile factories, killing nearly 60 percent of the river’s fish species and causing health problems for people who live along the banks of the polluted river.

In recent years, the Indonesian government has vowed to clean the Citarum River as studies from environmental groups had found that levels of lead in the river reached 1,000 times the U.S. standard for drinking water, but the problem has persisted due to the lack of coordination, maintenance and enforcement.

Yes, people still swim in it and use the water.

Fleck Control Valve Warranties

The generous “five-year warranty” on standard Fleck control valves doesn’t mean that the valve will be replaced or repaired for anything at all that goes wrong during the warranty period. In fact, most things that go wrong with filter and softener valves are regarded as normal wear and tear and are the responsibility of the owner.

Parts that are obviously defective are replaced through warranty. Examples would be a failed display screen or a burned-out transformer or a motor that stops working. In these cases, though, it is normally up to the owner to diagnose the problem and do the repair. You may have to send in the faulty part, pay shipping charges yourself, and wait for the replacement part.

This SXT control was sent to us for warranty repair. When we removed the screen cover, we found a small green frog, fried to a crisp.  Damage by green frogs is considered normal wear and tear and does not qualify for warranty replacement.

City Units vs. Well Units

Filters and softeners running on clean city water normally sail through the warranty period and last years beyond without a problem.  Units treating challenging well water issues like iron, manganese, heavy sediment, or extreme hardness, on the other hand, can be expected to need some maintenance from time to time. Harsh operating conditions cause problems that are regarded as normal wear and tear.

Iron-covered 5600 Control Valve. Can be restored by cleaning and seal/spacer replacement. Not covered by warranty.

Seals and Spacers

The most common control valve issue that well water users face is replacement of seals and spacers.  The seals and spacers that surround the inner piston are vulnerable to damage by adverse water conditions. If you are treating iron, you can be certain that you will eventually have seal and spacer replacement to perform. Seals and spacers are non-warranty parts that fall into the “normal wear and tear” category regardless of how long they last.  The manufacturer does not replace seals and spacers or reimburse for labor charges. The same normally applies to pistons, unless the piston is faulty when the control valve is new.

The difficulty of seal and spacer replacement for the three most popular Fleck residential control valves varies.  All can be repaired without removing the control valve from its tank, but some are much easier than others.

Seals and Spacers are relatively inexpensive parts ($20 and up). Pistons are more in the $50 range.

In order of replacement difficulty:

Fleck 2510: Special tools are not absolutely required, but highly recommended.  Both extraction and replacement of seals and spacers can be difficult without owning the “puller” and “stuffer” tools sold by Fleck.

Fleck 5600: No special tools needed and the job can be done by anyone with normal handyman skills.

Fleck 5810: Fleck’s newest valve is easiest to service. Seals and spacers are sold in a cartridge format and are easy to replace. No special tools needed. Note: 5810 has been discontinued.

Seal and Spacer replacement is explained in most Fleck control valve manuals, and online videos are plentiful. Parts are also easy to find.

Parts and tools for 5600 and 2510 valves.