Sudden and Unexplained Micro-Algae Outbreaks:
Sudden and unexplained Micro-Algae outbreaks even though in the instances when they occur, testing would seem to indicate that all water chemistry quality parameters (especially phosphates) are extremely low (for instance PO4 is around 0.03 ppm.) and within the recommended ranges a set of circumstances where micro-algae should not grow. This means that nitrates and silicates are low too. Such low phosphate and other nutrient concentrations and the fact that other water quality parameters are completely in line with generally recommended safe levels, should "not" give rise to the appearance of micro-algae "at all", yet hobbyists report that they nevertheless happen and often occur suddenly, at the most unexpected time.
This is happening to hobbyists with lots of experience and beginners alike. Everybody is, needless to say, stumped when this befalls them, even the experts.
This being the case, why do these micro-algae suddenly appear even though aquarium conditions and water quality do not account for such growth at all? Here is an explanation that can account for these outbreaks abeit not the only one.
It has been postulated, and proven, that the long term use of Kalkwasser precipitates phosphates out of the water and that these phosphate based compounds settle "on" and "in" the rock (live rock) in the aquarium, as well as "in" and "on" the substrate that may be present in the aquarium. This is the case too, of course if your tank contains Live Sand. In fact, Live Sand makes a real good settlement area for phosphate based compounds (all of them are complex compounds, a part of which is phosphate).
Since these compounds are "not" soluble at high pH levels they are really not a cause for concern as, in their insoluble state they are not available as nutrients for up-take by micro-algae and the growth of same. As long as they remain in a high pH area, they will not give rise to algal growth because the phosphate they contain is "bound" and thus not available to algae or for algae to grow. Over time they simply accumulate more and more in the tank as "insoluble matter" which can be siphoned out from time to time (not weekly, but monthly or every two months perhaps). As a matter of course anything that settles on the rock and on the sand should be siphoned out. Not only does this keep the water cleaner but it will prevent the cause for these sudden unexplained outbreaks of green undesirable algae.
Insoluble matter is of no concern, since it cannot affect tank conditions. In its insoluble state it is also inert and does not react in any way with the water in the aquarium. In this state it certainly cannot provide nutrients for micro-algae to grow profusely as is reported by hobbyists.
The reason for the growth of algae lies elsewhere. It is very much connected with the "settled" phosphate containing compounds.
Apparently situations occur whereby "certain" areas of the tank actually exhibit a different pH level than the one measured in the main water body of the aquarium. In this instance: lower and sometimes quite a bit lower than the aquarium's pH level. We are not aware of this because we do not measure the pH in those areas. We only measure the pH of the aquarium water itself. Where would this occur and why? Can this, in fact, occur at all? The answer is "yes" in all cases, as demonstrated by empirical evidence that such micro-algae outbreaks do occur. The use of KW is not the only reason that phosphate may precipitate out of the water. Other chemical reactions that occur in the tank can make this happen as well.
Many hobbyists have noted that such sudden growths have happened to them even though they have adhered to superior aquarium maintenance, husbandry techniques and practices. Their appearance is therefore not due to lack of maintenance or neglect of the tank and the water chemistry.
Do we have to accept these unexpected algae growths and outbreaks as a fact of life, something that can happen to any hobbyist at any given time? Or, is there some sort of reason or explanation for this growth?
Fortunately, the explanation is a lot simpler than one actually thinks. The remedies are not difficult to implement. The solution is not complicated and these outbreaks can be prevented.
whatever preciPhosphates that are "bound" in an insoluble form and are not available to algae "can" and "will" go into solution because of pH fluctuations in certain areas of the aquarium, areas where a much lower pH exists, or develops, than the actual pH of the aquarium itself.
These pH drops in certain areas are due to nothing more than basic chemistry principles. It is well documented in many publications that live and other rocks should be regularly cleaned off and that any precipitates should be removed. This subject hit more than one touchy area. These recommendations had to do mostly with removing organic material that may otherwise decompose. These regular cleanings have an additional benefit of removing insoluble phosphate based compounds, preventing them from fitting into the scenario described here.
When the pH drops in those areas of the aquarium, these insoluble compounds break up. Because they are in low pH areas the compounds dissociate, with the result that ortho-phosphate goes back into solution, giving rise to the sudden appearance of micro-algal growth, a growth that was totally "unexpected" and "unpredictable" given the tank's water quality conditions.
This falling pH syndrome occurs mainly in two types of areas in the aquarium: in the substrate (whatever its type) and in crevices in the live and other rock, present in the tank. Pollutants may build up in those areas and create conditions favorable for the pH to drop quite a bit (even though the drop is very localized and does not spread to the rest of the aquarium).
These localized drops in the pH level in these areas dissolves the phosphate based compounds that are present there, phosphate based compounds that were previously inert and now no longer are.
This process puts ortho-phosphate back into the water, making ortho-phosphate levels rise again. The rise can bring the PO4 level higher than the recommended level very easily if this break up of phosphate based compounds occurs in more than one area. This could liberate quite a bit of PO4 into the tank's water. If this scenario occurs in enough areas of the aquarium, enough phosphate will re-dissolve for micro-algae to suddenly start reappearing in the tank. Remember it does not take very much phosphate for micro-algae to grow. Levels as low as 0.03 ppm. can bring about outbreaks that then need to be eradicated. (CONT. PT-2)
Sudden and unexplained Micro-Algae outbreaks even though in the instances when they occur, testing would seem to indicate that all water chemistry quality parameters (especially phosphates) are extremely low (for instance PO4 is around 0.03 ppm.) and within the recommended ranges a set of circumstances where micro-algae should not grow. This means that nitrates and silicates are low too. Such low phosphate and other nutrient concentrations and the fact that other water quality parameters are completely in line with generally recommended safe levels, should "not" give rise to the appearance of micro-algae "at all", yet hobbyists report that they nevertheless happen and often occur suddenly, at the most unexpected time.
This is happening to hobbyists with lots of experience and beginners alike. Everybody is, needless to say, stumped when this befalls them, even the experts.
This being the case, why do these micro-algae suddenly appear even though aquarium conditions and water quality do not account for such growth at all? Here is an explanation that can account for these outbreaks abeit not the only one.
It has been postulated, and proven, that the long term use of Kalkwasser precipitates phosphates out of the water and that these phosphate based compounds settle "on" and "in" the rock (live rock) in the aquarium, as well as "in" and "on" the substrate that may be present in the aquarium. This is the case too, of course if your tank contains Live Sand. In fact, Live Sand makes a real good settlement area for phosphate based compounds (all of them are complex compounds, a part of which is phosphate).
Since these compounds are "not" soluble at high pH levels they are really not a cause for concern as, in their insoluble state they are not available as nutrients for up-take by micro-algae and the growth of same. As long as they remain in a high pH area, they will not give rise to algal growth because the phosphate they contain is "bound" and thus not available to algae or for algae to grow. Over time they simply accumulate more and more in the tank as "insoluble matter" which can be siphoned out from time to time (not weekly, but monthly or every two months perhaps). As a matter of course anything that settles on the rock and on the sand should be siphoned out. Not only does this keep the water cleaner but it will prevent the cause for these sudden unexplained outbreaks of green undesirable algae.
Insoluble matter is of no concern, since it cannot affect tank conditions. In its insoluble state it is also inert and does not react in any way with the water in the aquarium. In this state it certainly cannot provide nutrients for micro-algae to grow profusely as is reported by hobbyists.
The reason for the growth of algae lies elsewhere. It is very much connected with the "settled" phosphate containing compounds.
Apparently situations occur whereby "certain" areas of the tank actually exhibit a different pH level than the one measured in the main water body of the aquarium. In this instance: lower and sometimes quite a bit lower than the aquarium's pH level. We are not aware of this because we do not measure the pH in those areas. We only measure the pH of the aquarium water itself. Where would this occur and why? Can this, in fact, occur at all? The answer is "yes" in all cases, as demonstrated by empirical evidence that such micro-algae outbreaks do occur. The use of KW is not the only reason that phosphate may precipitate out of the water. Other chemical reactions that occur in the tank can make this happen as well.
Many hobbyists have noted that such sudden growths have happened to them even though they have adhered to superior aquarium maintenance, husbandry techniques and practices. Their appearance is therefore not due to lack of maintenance or neglect of the tank and the water chemistry.
Do we have to accept these unexpected algae growths and outbreaks as a fact of life, something that can happen to any hobbyist at any given time? Or, is there some sort of reason or explanation for this growth?
Fortunately, the explanation is a lot simpler than one actually thinks. The remedies are not difficult to implement. The solution is not complicated and these outbreaks can be prevented.
whatever preciPhosphates that are "bound" in an insoluble form and are not available to algae "can" and "will" go into solution because of pH fluctuations in certain areas of the aquarium, areas where a much lower pH exists, or develops, than the actual pH of the aquarium itself.
These pH drops in certain areas are due to nothing more than basic chemistry principles. It is well documented in many publications that live and other rocks should be regularly cleaned off and that any precipitates should be removed. This subject hit more than one touchy area. These recommendations had to do mostly with removing organic material that may otherwise decompose. These regular cleanings have an additional benefit of removing insoluble phosphate based compounds, preventing them from fitting into the scenario described here.
When the pH drops in those areas of the aquarium, these insoluble compounds break up. Because they are in low pH areas the compounds dissociate, with the result that ortho-phosphate goes back into solution, giving rise to the sudden appearance of micro-algal growth, a growth that was totally "unexpected" and "unpredictable" given the tank's water quality conditions.
This falling pH syndrome occurs mainly in two types of areas in the aquarium: in the substrate (whatever its type) and in crevices in the live and other rock, present in the tank. Pollutants may build up in those areas and create conditions favorable for the pH to drop quite a bit (even though the drop is very localized and does not spread to the rest of the aquarium).
These localized drops in the pH level in these areas dissolves the phosphate based compounds that are present there, phosphate based compounds that were previously inert and now no longer are.
This process puts ortho-phosphate back into the water, making ortho-phosphate levels rise again. The rise can bring the PO4 level higher than the recommended level very easily if this break up of phosphate based compounds occurs in more than one area. This could liberate quite a bit of PO4 into the tank's water. If this scenario occurs in enough areas of the aquarium, enough phosphate will re-dissolve for micro-algae to suddenly start reappearing in the tank. Remember it does not take very much phosphate for micro-algae to grow. Levels as low as 0.03 ppm. can bring about outbreaks that then need to be eradicated. (CONT. PT-2)
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