Why is my tank losing tannins
- Thread starter Hybridfish7
- Start date
Being organic compounds, Tannins degrade over a fairly short time, and in tanks need to be regularly replaced.
In my situation being in the rainy season, with my tank outside, under the influence of tannins that seep off dripping plants daily, I can barely see 3 inches into the tank.
Here are 2 studies that talk about tannin degradation.
Abstract: Tannin (Polyphenol) Stability in Aqueous Solutions ...scisoc.confex.com › crops › webprogram › Paper55514
Aerobic and anaerobic degradation of tannic acid on water ...www.scielo.br › scielo
In my situation being in the rainy season, with my tank outside, under the influence of tannins that seep off dripping plants daily, I can barely see 3 inches into the tank.
Here are 2 studies that talk about tannin degradation.
Abstract: Tannin (Polyphenol) Stability in Aqueous Solutions ...scisoc.confex.com › crops › webprogram › Paper55514
Aerobic and anaerobic degradation of tannic acid on water ...www.scielo.br › scielo
Ditto to the good advice above.
Also, tannins are being removed with the water changes, so if you want a certain level, you will need a constant source. The driftwood in the tank provides some, but it wears out continuously. In the forest streams, well there a forests that serve as source. Some people treat their water with peat moss or other means. I like the situation duanes describes, having the tanks outside. Not all can do that, unfortunately.
Also, tannins are being removed with the water changes, so if you want a certain level, you will need a constant source. The driftwood in the tank provides some, but it wears out continuously. In the forest streams, well there a forests that serve as source. Some people treat their water with peat moss or other means. I like the situation duanes describes, having the tanks outside. Not all can do that, unfortunately.
It's interesting that because another name for tannins are tannic acids, you would think pH would drop significantly with lots of tannins, and rise without them.
Soon after the rains started here, and my 180 gal tank became tea colored , I expected pH to drop, so did a few pH tests.
Here are the results.
Below ...Compare to a pH test from back in January, before the rains started, and the tank had few if any significant tannins dripping in
Below ....a shot from the same day in January showing the difference in water color from the one taken a few days ago, a few posts above.
There are factors that determine whether of not pH rises or falls.
Lack of pH drop may have to do with the waters buffering capacity.
If your waters buffering capacity (AKA alkalinity) is low, your pH may drop like a rock.
If your tap water alkalinity is high, the calcium in it prevents pH from falling.
Below is a test done about 3 years ago of my island tap water.
The 5th row down is Total Alkalinity and reads @ 100+ ppm of Alkalinity.
This is a fairly strong buffering capacity.
When i was living in Milwaukee, the tap water Alkalinity was slightly lower at around 90ppm, so easier to manipulate pH.
Soon after the rains started here, and my 180 gal tank became tea colored , I expected pH to drop, so did a few pH tests.
Here are the results.
Below ...Compare to a pH test from back in January, before the rains started, and the tank had few if any significant tannins dripping in
Below ....a shot from the same day in January showing the difference in water color from the one taken a few days ago, a few posts above.
There are factors that determine whether of not pH rises or falls.
Lack of pH drop may have to do with the waters buffering capacity.
If your waters buffering capacity (AKA alkalinity) is low, your pH may drop like a rock.
If your tap water alkalinity is high, the calcium in it prevents pH from falling.
Below is a test done about 3 years ago of my island tap water.
The 5th row down is Total Alkalinity and reads @ 100+ ppm of Alkalinity.
This is a fairly strong buffering capacity.
When i was living in Milwaukee, the tap water Alkalinity was slightly lower at around 90ppm, so easier to manipulate pH.
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Does anyone know if tannins, being carbon rich organic molecules, can help feed anerobic bacteria needed for "full cycle" nitrate removal? The bacteria would consume nitrate, using it to oxidize the carbon within the tannin into CO2. I have also seen my tannins go from extremely high to virtually gone within a few days.