Hello Readers:

Since our last post (which was actually our first post), we’ve made excellent progress in solving the possible and probable causes of the somewhat rare and perplexing condition, becoming well-known as the Mysterious White Slime Metabolism.  This metabolism has recently occurred in an aquarium of one of our clients. (See original blog)

Out of the blue I received a call from a service tech who services the Boca Raton area.  He has been challenged by an identical situation in one of his clients’ office and was at a loss and the problem seemed to be spreading to other aquariums in the building.  (This client has many aquariums in their offices which of course includes an ocean theme).  Although the slime and the results of the slime appear to be almost identical, it looks as though the conditions leading up to the appearance looks to be slightly different. However, there are some similar factors in both cases.

Previously we spoke of the bacteria, Alcaligenes faecalis as a possible cause of the slime.  This bacterium is an aerobic heterotroph considered to be ubiquitous,  which creates the slime as a metabolic by-product.  Under the proper conditions of elevated phthalates and VOCs, these bacteria bloom and begin to dominate the fauna associated with our aquariums.   Soon, everything becomes coated with the thick slime, which can begin to smother corals and eventually rob oxygen to the point of fish dying from anoxia.  Although true identification requires culturing the bacteria, costs are prohibitive, and probably unnecessary.  It is also secondary to finding the solution of eradicating the slime.  This slime begins as an opaque or semi transparent white color, but soon becomes brown to dark brown as it thickens and collects organic waste and debris.

Fortunately, we were able to isolate a common denominator in both cases.  This link was the presence and increasing use of plug-in room deodorizers.  After careful observation and client interviews, it was determined that there were many of these units at both locations, in use for different reasons.  In the case of my client (a residential location), the owners have a couple of dogs and a few cats, and the room deodorizers have been used to neutralize undesirable odors from the air in the home.  In use for a long time, there has not been a problem until the carpets in their home were “dry-cleaned”.  Two days later, the slime appeared, quickly becoming an obvious problem overnight.  Likewise, although plug –in deodorizers have been intermittently used at the dental office for a very long time, the slime only appeared after one of their air conditioners caught fire, which resulted in a great deal of smoke pumping into the office.  Contained in the smoke was a large amount of the two compounds, since they are used in the manufacturing of plastics and wire coatings.  Because of the fire, the office required evacuation, and remedial smoke damage was initiated.  Of course, our conclusion is that the phthalates and VOCs generated In both cases caused the system nutrient levels to reach the critical threshold.  As a result of the carpet cleaning and the fire, the first appearance of the slime began immediately after an event had occurred, which I call the catastrophic initiation event.

My research regarding the problem led me to personal discussions with Dr. Tim Hovanec, microbiologist, innovator and aquarist.  He just happens to own Dr. Tim’s Aquatics, a company engaged in the research, development and production of biological products, designed to work harmoniously in fresh water and marine aquariums by utilizing (among other things) naturally occurring bacteria and enzymes.  Although he had not experienced quite what we were going through, he generously shared with me his experiences regarding such slime in aquariums, and sent me some studies regarding the presence of organic compounds (known as phthalates and VOCs) as causative agents.  The plug-in deodorizers contain a fair amount of both compound groups, but apparently not enough to cause the bloom of the slime-producing bacteria.  Our data indicates that the catastrophic initiation event was then required to put the nutrient level over the threshold concentration point, which then allowed the slime-producing heterotrophic bacteria to bloom.

The deeper my research became, the more astonished I was at the revelations that I discovered.  Look for our results in the next post.  Thanks for reading – Lance

Wikipedia defines phthalates as:

“Phthalates, or phthalate esters, are esters of phthalic acid and are mainly used as plasticizers (substances added to plastics to increase their flexibility, transparency, durability, and longevity). They are primarily used to soften polyvinyl chloride. Phthalates are being phased out of many products in the United States and European Union over health concerns”.

Wikipedia lists the uses of phthalates as follows:

“Phthalates are used in a large variety of products, from enteric coatings of pharmaceutical pills and nutritional supplements to viscosity control agents, gelling agents, film formers, stabilizers, dispersants, lubricants, binders, emulsifying agents, and suspending agents. End applications include adhesives and glues, agricultural adjuvants, building materials, personal care products, medical devices, detergents and surfactants, packaging, children’s toys, modelling clay, waxes, paints, printing inks and coatings, pharmaceuticals, food products, and textiles…”

Additionally, they go on to say:

“Phthalates are used in a variety of household applications such as shower curtains, vinyl upholstery, adhesives, floor tiles, food containers and wrappers, and cleaning materials. Personal care items containing phthalates include perfume, eye shadow, moisturizer, nail polish, liquid soap, and hair spray. They are also found in modern electronics and medical applications such as catheters and blood transfusion devices. The most widely-used phthalates are the di-2-ethyl hexyl phthalate (DEHP), the diisodecyl phthalate (DIDP) and the diisononyl phthalate (DINP). DEHP is the dominant plasticizer used in PVC due to its low cost. Benzylbutylphthalate (BBP) is used in the manufacture of foamed PVC, which is mostly used as a flooring material. Phthalates with small R and R’ groups are used as solvents in perfumes and pesticides.

Also defined by Wikipedia, a VOC is:

“Volatile organic compounds (VOCs) refers to organic chemical compounds which have significant vapor pressures and which can affect the environment and human health. VOCs are numerous, varied, and ubiquitous. Although VOCs include both man-made and naturally occurring chemical compounds, it is the anthropogenic VOCs that are regulated, especially for indoors where concentrations can be highest. VOCs are typically not acutely toxic but have chronic effects. Because the concentrations are usually low and the symptoms slow to develop, analysis of VOCs and their effects is a demanding area”…

“… A major sources of man-made VOC’s are solvents, especially paints and protective coatings. Solvents are required to spread the protective or decorative film. Approximately 12 billion liters of paints are produced annually. Typical solvents are aliphatic hydrocarbons, ethyl acetate, glycol ethers, and acetone. Motivated by cost, environmental concerns, and regulation, the paint and coating industries are increasingly shifting toward aqueous solvents.”

It would appear as though the levels of VOCs and phthalates reached the critical concentration as a result of the carpet cleaning and the air conditioning fire, since the VOCs and phthalates are found in both cleaning products (the carpet cleaning solutions), as well as plastics (wires, parts found in air conditioners).  In fact, Wikipedia says that the majority of VOCs occur naturally, arising from plants in nature.

Also of concern:

“… Chlorofluorocarbons, which are banned or highly regulated, were widely used cleaning products and refrigerants. Tetrachloroethene is used widely in dry cleaning and by industry. Industrial use of fossil fuels produces VOCs either directly as products (e.g. gasoline) or indirectly as byproducts (e.g. automobile exhaust).”

Finally, Wikipedia lists:

“… Many building materials such as paints, adhesives, wallboards, and ceiling tiles slowly emit formaldehyde, which irritates the mucous membranes and can make a person irritated and uncomfortable. Formaldehyde emissions from wood are in the range of 0.02 – 0.04 ppm. Relative humidity within an indoor environment can also affect the emissions of formaldehyde. High relative humidity and high temperatures allow more vaporization of formaldehyde from wood-materials. There are also many sources of VOCs in office buildings, which include new furnishings, wall coverings, and office equipment such as photocopy machines which can off-gas VOCs into the air.”

As we have removed the sources of phthalates and are working to minimize VOCs in both locations, the slime production appears to be slowly reducing.  The controlling factors, however, are the heterotrophic bacteria that we are now introducing, which will actually break down the slime and out-compete the slime-producing bacteria for food.  In this fashion, we will be able to control the slime-producing heterotrophs and keep them in check.  Dr. Hovanec has recommended the use of Re-Fresh initially at a dose of 5-ml per 10-gallons every other day for 7-10 days.  He goes on to say that adding 35% hydrogen peroxide at a concentration of 2-3 mls per 10-gallons in conjunction with the Re-Fresh would be very beneficial;  however, our experiences indicate that some corals (mostly soft, but some stony) and certain species of fish (large angels in particular) can react adversely to the concentrated H2O2, so be careful with the 35% stuff.  At that point, the slime should have been broken down, and we would change the additive to Waste-Away.  Also on an every other day basis, the Waste-Away would be used at a 5-ml per 10-gallon dose for two treatments, then raised to 10-ml per 5-gallons after that.  Once the slime has been eliminated, the Waste-Away can be used as a routine maintenance product.

So at this time we are in the process of dosing our aquariums with the Re-Fresh, and the slime has greatly been reduced already, after only three doses of the product.  Over time, it will break down the organic detritus and other celluloid waste, which builds up in the gravel and on the live rock in our aquariums, making our jobs easier and our aquarium inhabitants happier and healthier.  Based on our experience here, we intend to continue using the products on a maintenance basis in the future, for sure.

Next entry- the conclusion of the mysterious white slime metabolism.