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Bacteria Boosters

Biological Additives and the Damage They Can Cause to a Healthy Aquarium

(The First Tank Guide)

Bacteria boosters or biological filter starters or enhancers are both unnecessary and can be damaging to the long-time stability of your aquarium. These bacteria boosters are supposedly colonies of bacteria that will get your tank cycled or increase your biological filter's capacity. But this is nearly always not the case.

The bacteria you need in your biological filter needs two things to stay alive. One is food - in their case ammonia and nitrite - and the other is oxygen. However this bacteria is shipped in sealed plastic bottles - which means limited food and no source of air. Yes, the bottles can be filled with ammonia and oxygen, but there is not a recurring supply, so once the air or food is exhausted, it is exhausted. It seems, in most cases, you are receiving cultures of dead good bacteria, possibly with a living colony of bad anaerobic (without oxygen) bacteria.

This bad bacteria is the same bacteria that you do not want to begin growing in your aquarium gravel, and is part of why it is important to clean the gravel as part of your weekly water change even if you are not using an under gravel filter. Though this bad bacteria will die shortly in the aerobic environment of a well circulating, well maintained fish tank, it is quite possible that it has produced toxins that you are willingly introducing to your fish tank. These toxins are exactly why you want to make sure that these anaerobic bacteria do not colonize a hidden corner of your fish tank. The toxins produced by anaerobic bacteria in the bottle (or in the tank) are why using a bacteria booster to try to cycle your aquarium can make the cycling process take several months longer, as each dose of the toxic bacteria kills off the majority of the filter, forcing the process to start over.

Furthermore, the good bacteria has to have been packed with food for it to survive, and this food is fish waste, so you are adding unnecessary fish waste to your tank when you add this bacteria booster, should the food not yet all be consumed. Also, the if the bacteria in the bottle are already dead—which is most likely the case—you are just adding that much more decaying organic matter to he tank. Your fish should be providing your tank with more than enough waste to keep the cycle going, and adding more is unnecessary and undesired.

These bacteria booster are also unnecessary because the bacteria that they are providing for you are ubiquitous—they are already available everywhere in the environment, so they are readily available to your fish tank. Once they get into the fish tank and have access to that food source, they will begin to multiply. This is what is happening when your tank is cycling.

As far as adding more bacteria booster with each water change, this is only viable as a money making scheme for the manufacturers of the products. First, assuming that the bacteria are actually live in the bottle (and hoping that they are not so far gone as to be replaced with their toxic anaerobic counterparts), your tank can only support so much bacteria in its biological filter. The amount of bacteria that your tank can sustain is governed by several factors, including:

So, if your tank has finished cycling, it will have as much of a bacteria colony as it can support, based on the resources provided. Adding more bacteria to the system will only result in a die-off of bacteria within the tank as a whole and a temporarily loss in stability of the biological filter until the system can re-assert itself.

"Thank you so much. You're the only person that has actually considered the situation and not just said, "Mehh, wait a bit longer.""
July 2, 2009
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January 14, 2007
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