This is my third article in a series known as "Good To Know" (abbr. GTK), where I will research and attempt to clarify some common mistakes, myths and fish hobby anecdotes for those who are new, and for the vets who have always wondered what information is truly correct and reliable.
The main theme of this article is to help both new and seasoned aquarist understand the bacteria in their tanks. A large amount of misinformation currently circulates the “non-fish junky” level of aquarist population, leading to poor maintenance, understanding and tank husbandry. Dr. Tim Hovanec, a microbiologist and fish hobbyist, is currently the leading mind in this field and thus, will be considered the primary source for information regarding bacteria in aquariums. Dr. Hovanec is best known in the community as Dr. Tim, and will thus be referred to as so through this article.
Beginner’s Guide to Bacteria in the Aquarium
Ammonia molecule - NH3
Photo Credit: PondPlace.com
There is a difference between Nitrifying bacteria, and Sludge Degrading bacteria in aquariums. Many hobbyists will mistakenly confuse the two, especially in times when cloudy water is an issue. Often, hobbyist will be told that the bloom is actually Nitrifying bacteria which is exploding in number due to a waste issue in the tank. This is only partly true; the bacteria you are seeing is exploding in population due to excess waste, but this bacteria is a different type of bacteria and is sometimes referred to as “bad” bacteria because it can out compete Nitrifying bacteria1.
Not all “Bacteria in a Bottle” products are made the same. When Dr. Tim began researching his PhD dissertation, he made some pretty important discoveries regarding bacteria in aquariums. Dr. Tim, in an interview with Mr. Saltwater Tank entitled “Bacteria in a Bottle: Snake Oil or Worth Trusting”2, commented on how he came to understand why many of these products were failing: “All the nitrifiers had bacteria that came from waste water treatment, they didn’t have aquarium bacteria, they’re the wrong ones. They [customers] would add the bottle and think ‘oh, they’re all dead’. No, they’re the wrong bacteria. They are all nitrifiers, but certain nitrifiers live in high ammonia and high nitrite concentrations like a wastewater treatment plant. We don’t have those concentrations [in aquariums]. We have very low concentrations. That’s a different species of ammonia oxidizer and a different species of nitrite oxidiers”. Dr. Tim explains he was looking for the old-school bacteria (Nitrosomas europea And Nitrobacter sp.) but found none or very inconsequential amounts, and ended up concluding that it was Nitrosomas marina which oxidized ammonia and Nitrospira sp and Nitrosococcus sp. which converts Nitrite to Nitrate in a healthy aquarium. Dr. Tim’s bacteria, which have gained a good reputation online, can be ordered online at: http://store.drtimsaquatics.com/ or can be found at other hobby related retailers.
Tetra SafeStart is the only product, other than Dr. Tim's One and Only Live Bacteria, known to carry the proper cycling bacteria. Most other products carry the water treatment plant bacteria which is useless in low concentration environments like and aquarium.
Photo Credit: AquariumWiki.com
Sludge degrading bacteria are not, in most cases, beneficial to aquariums. Sludge degrading bacteria have a limited role in a healthy aquarium. While these bacteria do eat organic compounds (such as fish mulm), they should be used in conjunction with a bottle bacteria product (see below) or water changes as these bacteria only break down waste into ammonia. Test your tank when using these products to ensure that your tank can handle the excess ammonia and convert it quickly.
Sludge degrading products also have an added benefit whereby they out compete “bad” bacteria by cultivating a much less harmful species. This is called Competitive Exclusion, which is defined by AquariumWiki3, “By adding known harmless waste eating bacteria in large numbers the added bacteria out competes any existing bad bacteria for the nutrients in the tank and therefore is a safe and effective way to starve off infectious bacteria. In the medical industry this technique is called 'bacterial interference' and is used to displace pathogens by using harmless bacteria.” These types of products are usually referred to as “Zymes” such as Stress Zyme by API, yet some Waste reduction products also have this added effect.
Never overdose these products as the new bacteria can starve out your good bacteria through oxygen and nutrient depletion causing a tank crash.
Example of a product which contains sludge degrading heterotrophic bacteria.
Photo Credit: SwellUK.com
Boil your dried out filter media to help ward off bad bacteria. Unfortunately for hobbyists, the good nitrifying bacteria cannot survive when dried out. However, the bad heterotrophic bacteria can4. To ensure that the good bacteria has a fighting chance at colonising all your media, boil and bacteria housing media once it has dried out to eliminate the bad bacteria. Also, any media which has been standing in stagnant water for more than approx. 15-20hrs without oxygenation should be boiled in ideal circumstances.
Forget the shrimp rotting method of cycling.
So we’ve been discussing how so called “bad” bacteria can out-compete good bacteria for nutrients, oxygen, and space. By using a piece of shrimp, you are indeed adding a source of ammonia, but first, you are stimulating a massive explosion in growth of organic compound devouring bad bacteria, which will quickly colonise much of your available media and tank before the good bacteria can find a place to begin breaking down the subsequent ammonia spike. Aside from this competition aspect, a full grown shrimp in a sterile tank will likely cause an ammonia spike over 5ppm5, which actually inhibits the growth of good bacteria. Which brings us to our next point…
When cycling a tank, keep ammonia below 5ppm. As we’ve just mentioned, Dr. Tim explains in Episode 22 of Aquariumania on Pet Life Radio5, that having an ammonia reading above 5ppm can actually inhibit the growth of nitrifying bacteria. In extreme cases, Nitrosomas europea bacteria can become the dominant species, which will not be sustainable in a low concentration system like an aquarium. Thus, the cycle will be prolonged as some high range ammonia oxidizers come and go and the real aquarium bacteria takes hold. If your ammonia level reaches over 5ppm, do water changes to correct this problem.
Environmental conditions can effect the quality of bottled bacteria. Dr. Tim states on his website6 that, “Environmental conditions can cause bad batches. The first condition is being exposed to temperatures outside the range they can survive. If the liquid in the bottle freezes the nitrifying bacteria are killed. It don’t matter the brand – freezing kills the nitrifying bacteria. High temperatures also can kill or damage nitrifying bacteria. If the bottle is exposed to 110°F for a day or so the bacteria can be killed. Prolonged exposure to temperatures over 95°F drastically reduces the shelf life of nitrifying bacteria.” Dr. Tim goes on to recommend checking the best before date and also explains that refrigerating the bacteria can help keep the bacteria fresher and more viable longer.
This concludes the beginner portion of the bacterial article. For those wanting to dig deeper into the subject, I will be posting a new article which discusses the more advanced topics such as Autotroph vs Heterotroph, Probiotics, Vodka dosing, Denitrificaton, Building a denytrifier, Nitrosomas Europea vs Nitrosomas marina and Faculative vs Obliogated Hetertrophs.
For more information on some of the products mentioned, an article explaining the use of common aquarium products is also in the making.
APPENDIX
The main theme of this article is to help both new and seasoned aquarist understand the bacteria in their tanks. A large amount of misinformation currently circulates the “non-fish junky” level of aquarist population, leading to poor maintenance, understanding and tank husbandry. Dr. Tim Hovanec, a microbiologist and fish hobbyist, is currently the leading mind in this field and thus, will be considered the primary source for information regarding bacteria in aquariums. Dr. Hovanec is best known in the community as Dr. Tim, and will thus be referred to as so through this article.
Beginner’s Guide to Bacteria in the Aquarium
Ammonia molecule - NH3
Photo Credit: PondPlace.com
There is a difference between Nitrifying bacteria, and Sludge Degrading bacteria in aquariums. Many hobbyists will mistakenly confuse the two, especially in times when cloudy water is an issue. Often, hobbyist will be told that the bloom is actually Nitrifying bacteria which is exploding in number due to a waste issue in the tank. This is only partly true; the bacteria you are seeing is exploding in population due to excess waste, but this bacteria is a different type of bacteria and is sometimes referred to as “bad” bacteria because it can out compete Nitrifying bacteria1.
Not all “Bacteria in a Bottle” products are made the same. When Dr. Tim began researching his PhD dissertation, he made some pretty important discoveries regarding bacteria in aquariums. Dr. Tim, in an interview with Mr. Saltwater Tank entitled “Bacteria in a Bottle: Snake Oil or Worth Trusting”2, commented on how he came to understand why many of these products were failing: “All the nitrifiers had bacteria that came from waste water treatment, they didn’t have aquarium bacteria, they’re the wrong ones. They [customers] would add the bottle and think ‘oh, they’re all dead’. No, they’re the wrong bacteria. They are all nitrifiers, but certain nitrifiers live in high ammonia and high nitrite concentrations like a wastewater treatment plant. We don’t have those concentrations [in aquariums]. We have very low concentrations. That’s a different species of ammonia oxidizer and a different species of nitrite oxidiers”. Dr. Tim explains he was looking for the old-school bacteria (Nitrosomas europea And Nitrobacter sp.) but found none or very inconsequential amounts, and ended up concluding that it was Nitrosomas marina which oxidized ammonia and Nitrospira sp and Nitrosococcus sp. which converts Nitrite to Nitrate in a healthy aquarium. Dr. Tim’s bacteria, which have gained a good reputation online, can be ordered online at: http://store.drtimsaquatics.com/ or can be found at other hobby related retailers.
Tetra SafeStart is the only product, other than Dr. Tim's One and Only Live Bacteria, known to carry the proper cycling bacteria. Most other products carry the water treatment plant bacteria which is useless in low concentration environments like and aquarium.
Photo Credit: AquariumWiki.com
Sludge degrading bacteria are not, in most cases, beneficial to aquariums. Sludge degrading bacteria have a limited role in a healthy aquarium. While these bacteria do eat organic compounds (such as fish mulm), they should be used in conjunction with a bottle bacteria product (see below) or water changes as these bacteria only break down waste into ammonia. Test your tank when using these products to ensure that your tank can handle the excess ammonia and convert it quickly.
Sludge degrading products also have an added benefit whereby they out compete “bad” bacteria by cultivating a much less harmful species. This is called Competitive Exclusion, which is defined by AquariumWiki3, “By adding known harmless waste eating bacteria in large numbers the added bacteria out competes any existing bad bacteria for the nutrients in the tank and therefore is a safe and effective way to starve off infectious bacteria. In the medical industry this technique is called 'bacterial interference' and is used to displace pathogens by using harmless bacteria.” These types of products are usually referred to as “Zymes” such as Stress Zyme by API, yet some Waste reduction products also have this added effect.
Never overdose these products as the new bacteria can starve out your good bacteria through oxygen and nutrient depletion causing a tank crash.
Example of a product which contains sludge degrading heterotrophic bacteria.
Photo Credit: SwellUK.com
Boil your dried out filter media to help ward off bad bacteria. Unfortunately for hobbyists, the good nitrifying bacteria cannot survive when dried out. However, the bad heterotrophic bacteria can4. To ensure that the good bacteria has a fighting chance at colonising all your media, boil and bacteria housing media once it has dried out to eliminate the bad bacteria. Also, any media which has been standing in stagnant water for more than approx. 15-20hrs without oxygenation should be boiled in ideal circumstances.
Forget the shrimp rotting method of cycling.
So we’ve been discussing how so called “bad” bacteria can out-compete good bacteria for nutrients, oxygen, and space. By using a piece of shrimp, you are indeed adding a source of ammonia, but first, you are stimulating a massive explosion in growth of organic compound devouring bad bacteria, which will quickly colonise much of your available media and tank before the good bacteria can find a place to begin breaking down the subsequent ammonia spike. Aside from this competition aspect, a full grown shrimp in a sterile tank will likely cause an ammonia spike over 5ppm5, which actually inhibits the growth of good bacteria. Which brings us to our next point…
When cycling a tank, keep ammonia below 5ppm. As we’ve just mentioned, Dr. Tim explains in Episode 22 of Aquariumania on Pet Life Radio5, that having an ammonia reading above 5ppm can actually inhibit the growth of nitrifying bacteria. In extreme cases, Nitrosomas europea bacteria can become the dominant species, which will not be sustainable in a low concentration system like an aquarium. Thus, the cycle will be prolonged as some high range ammonia oxidizers come and go and the real aquarium bacteria takes hold. If your ammonia level reaches over 5ppm, do water changes to correct this problem.
Environmental conditions can effect the quality of bottled bacteria. Dr. Tim states on his website6 that, “Environmental conditions can cause bad batches. The first condition is being exposed to temperatures outside the range they can survive. If the liquid in the bottle freezes the nitrifying bacteria are killed. It don’t matter the brand – freezing kills the nitrifying bacteria. High temperatures also can kill or damage nitrifying bacteria. If the bottle is exposed to 110°F for a day or so the bacteria can be killed. Prolonged exposure to temperatures over 95°F drastically reduces the shelf life of nitrifying bacteria.” Dr. Tim goes on to recommend checking the best before date and also explains that refrigerating the bacteria can help keep the bacteria fresher and more viable longer.
Mr. Saltwater Tank's interview with Dr. Tim.
This concludes the beginner portion of the bacterial article. For those wanting to dig deeper into the subject, I will be posting a new article which discusses the more advanced topics such as Autotroph vs Heterotroph, Probiotics, Vodka dosing, Denitrificaton, Building a denytrifier, Nitrosomas Europea vs Nitrosomas marina and Faculative vs Obliogated Hetertrophs.
For more information on some of the products mentioned, an article explaining the use of common aquarium products is also in the making.
APPENDIX
5- Pet Life Radio - Aquariumania - Episode 22 - The Good, the Bad and the Not-so-Ugly Truths about Aquarium Bacteria
SOURCES
AquariumWiki.com
(http://theaquariumwi...-Safestart1.jpg)
AquariumWiki.com – Bacteria
(http://theaquariumwiki.com/Bacteria)
AquariumWiki.com – Competetive Exclusion
(http://theaquariumwi...itive_Exclusion)
DrTimsAquatics.com – Bacteria Mixtures
(http://www.drtimsaqu...s-work-provided)
Kmuda. Oscarfish.com - Autotrophic Nitrifying Bacteria and Their Practical Application in a Freshwater Aquarium
(http://www.oscarfish...-manifesto.html)
Kmuda. Oscarfish.com - Heterotrophic Bacteria and Their Practical Application in a Freshwater Aquarium
(http://www.oscarfish...c-bacteria.html)
MrSaltwaterTank.com – Bacteria in a Bottle: Snake Oil or Worth Trusting?
(http://www.mrsaltwat...worth-trusting/)
PondPlace.com
(http://www.pondplace...n%20Diagram.png)
SwellUK.com
(http://www.swelluk.c...ste-control.jpg)
AquariumWiki.com
(http://theaquariumwi...-Safestart1.jpg)
AquariumWiki.com – Bacteria
(http://theaquariumwiki.com/Bacteria)
AquariumWiki.com – Competetive Exclusion
(http://theaquariumwi...itive_Exclusion)
DrTimsAquatics.com – Bacteria Mixtures
(http://www.drtimsaqu...s-work-provided)
Kmuda. Oscarfish.com - Autotrophic Nitrifying Bacteria and Their Practical Application in a Freshwater Aquarium
(http://www.oscarfish...-manifesto.html)
Kmuda. Oscarfish.com - Heterotrophic Bacteria and Their Practical Application in a Freshwater Aquarium
(http://www.oscarfish...c-bacteria.html)
MrSaltwaterTank.com – Bacteria in a Bottle: Snake Oil or Worth Trusting?
(http://www.mrsaltwat...worth-trusting/)
PondPlace.com
(http://www.pondplace...n%20Diagram.png)
SwellUK.com
(http://www.swelluk.c...ste-control.jpg)
No comments:
Post a Comment