Anaerobic Bacteria of Water & Soils


May 20, 2022

You’ve probably heard these terms:

Sulfate-Reducing Microorganisms

Sulfate Reducing Bacteria (SRB)

Turf Slosh

Root Rot

Black Layer

Organic Matter

Rotten Egg / Stinky Feet odor

Hydrogen Sulfide Gas (H2S)

Sulfurous Acids

The lethality of H2S to humans commonly posing challenges in manholes, sewer lines and under ground wells of all sorts.

The safety training of H2S and creation of H2S detectors to prevent fatalities.

Have you ever observed roots of plants or turf in soils laden with black layer, sustaining vegetation?

Below you will find how water retention, that constant wet area, that non-draining slosh, odor and or vegetation challenge is likely caused by “compromised infiltration” followed by bacteria colonization, namely sulfate reducing bacteria, also referred to as SRB, and commonly mistakenly identified as black layer and or organic matter.

It’s not so much the bacteria that is the problem, as are its exudates, its waste products, which are water, sulfurous acids and toxic / lethal hydrogen sulfide gas. The gas itself can be non-detected by human smell and be lethal to vegetation and humans.

Mitigating the problem can be nearly impossible as the bacteria feed on common water and soil products including sulfur, sulfate and possible manganese and iron, turning waters both above ground and in soils, septic, then exuding its toxins. These bacteria, in ideal circumstances of moisture and temperature, replicate exponentially, and about the only way to minimize them is through continuous oxygenation or oxidation. Mitigating the organisms on non-porous surfaces like ceramic tile, is a feat in itself.

Below are details about SRB and how they compromise our world of soil, water vegetation vitality and crop production and how WaterSOLV BC, also perhaps in combination with other catalysts, can be used effectively and efficiently in a soil and water treatment program.


When you see accumulations Sulfur, Sulfate, Zinc, Iron and or Manganese in your soils, or visualize a darkened hue of your soils, and or odor, the sooner you address the problem the better as the bacteria is growing exponentially. Desulfovibrio vulgaris is the best-studied sulfate-reducing microorganism species.

Sulfate-reducing microorganisms (SRM) or sulfate-reducing prokaryotes (SRP) are a group composed of sulfate- reducing bacteria (SRB) and sulfate-reducing archaea (SRA), both of which can perform anaerobic respiration utilizing sulfate (SO2−4) as terminal electron acceptor, reducing it to hydrogen sulfide (H2S). Therefore, these sulfidogenic microorganisms "breathe" sulfate rather than molecular oxygen (O2), which is the terminal electron acceptor reduced to water (H2O) in aerobic respiration.

HCT States: Sulfate and sulfur are food sources. Exudates, sulfurous acid, dissolves scale, minerals and metals, H2S is hydrogen sulfide gas, and is lethal to humans as well as vegetation. The H2O respiration is an example of “slosh” in turf. A stinky odor is the gas of the hydrogen sulfide. WaterSOLV BC overcomes these conditions. With Curative, the BC is catalyzed, even more effective.

Sulfate-reducing microorganisms can be traced back to 3.5 billion years ago and are considered to be among the oldest forms of microbes, having contributed to the sulfur cycle soon after life emerged on Earth.

Many organisms reduce small amounts of sulfates in order to synthesize sulfur-containing cell components; this is known as assimilatory sulfate reduction. By contrast, the sulfate-reducing microorganisms considered here reduce sulfate in large amounts to obtain energy and expel the resulting sulfide as waste; this is known as dissimilatory sulfate reduction. They use sulfate as the terminal electron acceptor of their electron transport chain. Most of them are anaerobes; however, there are examples of sulfate-reducing microorganisms that are tolerant of oxygen, and some of them can even perform aerobic respiration.

No growth is observed when oxygen is used as the electron acceptor. In addition, there are sulfate-reducing microorganisms that can also reduce other electron acceptors, such as fumarate, nitrate (NO−3), nitrite (NO−2), ferric iron (Fe3+), and dimethyl sulfoxide (DMSO).

HCT States: Hence the value of WaterSOLV BC and Curative as a catalyst, which degrades to dissolved oxygen and water.

In terms of electron donor, this group contains both organotrophs and lithotrophs. The organotrophs oxidize organic compounds, such as carbohydrates, organic acids (such as formate, lactate, acetate, propionate, and butyrate), alcohols (methanol and ethanol), aliphatic hydrocarbons (including methane), and aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene). The lithotrophs oxidize molecular hydrogen (H2), for which they compete with methanogens and acetogens in anaerobic conditions.

HCT States: Which in turn can lead towards the nutritional sources of iron reducing bacteria and bio-films. microorganisms can directly use metallic iron (Fe0, also known as zerovalent iron, or ZVI) as electron donor, Some sulfate-reducing oxidizing it to ferrous iron (Fe2+).

The toxic hydrogen sulfide is a waste product of sulfate-reducing microorganisms; its rotten egg odor is often a marker for the presence of sulfate-reducing microorganisms in nature. Sulfate-reducing microorganisms are responsible for the sulfurous odors of salt marshes and mud flats. Much of the hydrogen sulfide will react with metal ions in the water to produce metal sulfides. These metal sulfides, such as ferrous sulfide (FeS), are insoluble and often black or brown, leading to the dark color of sludge.

During the Permian–Triassic extinction event (250 million years ago) a severe anoxic event seems to have occurred (National Geographic - The Cosmos) where these forms of bacteria became the dominant force in oceanic ecosystems, producing copious amounts of hydrogen sulfide.

Sulfate-reducing bacteria also generate neurotoxic methylmercury as a byproduct of their metabolism, through methylation of inorganic mercury present in their surroundings. They are known to be the dominant source of this bioaccumulative form of mercury in aquatic systems.

Economic Importance