Can nutrient removal by chaeto be quantified?

[TWYOUNG]

I there any way to determine how many mgs of nitrate or phosphate is contained in a specific weight of macro alga? . I remove about 400 grams of chaeto per month and wondered if I can determine how many mgs of nitrate and phosphate this represents.

 

[The_Paradox]

Dose up a separate tank to a known value and add a known weight of Chaeto. Track the values as the Chaeto mass increases in 100g intervals. Repeat a few times if you want a higher confidence. This will still have some variables but probably the most accurate at home method. Is that or make Chaeto mash.

 

[GARRIGA]

Chaetomorpha linum in the bioremediation of aquaculture wastewater: Optimization of nutrient removal efficiency at the laboratory scale

Marine pollution from aquaculture wastewater is a widespread and increasing ecological problem. Algae, with their ability to remove surplus nutrients …

www.sciencedirect.com

Been studied extensively but I get headaches reading these papers. Have fun.

 

[TWYOUNG]

Dose up a separate tank to a known value and add a known weight of Chaeto. Track the values as the Chaeto mass increases in 100g intervals. Repeat a few times if you want a higher confidence. This will still have some variables but probably the most accurate at home method. Is that or make Chaeto mash.

I was hoping someone had done this already lol!

 

[TWYOUNG]

Chaetomorpha linum in the bioremediation of aquaculture wastewater: Optimization of nutrient removal efficiency at the laboratory scale

Marine pollution from aquaculture wastewater is a widespread and increasing ecological problem. Algae, with their ability to remove surplus nutrients …

www.sciencedirect.com

Been studied extensively but I get headaches reading these papers. Have fun.

Thanks, I'll check it out.

 

[Randy Holmes-Farley]

Yes, these studies have been done.

Phosphate in the Reef Aquarium

The phosphorus atom is one of living matter's basic building blocks. It is present in every living creature and in every reef aquarium's water. Unfortunately, it is often present in excess in reef aquaria, and that excess has the potential to cause at least two substantial problems for...

www.reefedition.com

For those interested in knowing how much phosphorus is being exported by macroalgae, this free PDF article in the journal Marine Biology has some important information. It gives the phosphorus and nitrogen content for nine different species of macroalgae, including many that reefkeepers typically maintain. For example, Caulerpa racemosa collected off Hawaii contains about 0.08% phosphorus by dry weight and 5.6% nitrogen. Harvesting 10 grams (dry weight) of this macroalgae from an aquarium would be the equivalent of removing 24 mg of phosphate from the water column. That amount is the equivalent of reducing the phosphate concentration from 0.2 ppm to 0.1 ppm in a 67-gal. aquarium. All of the other species tested gave similar results (plus or minus a factor of two). Interestingly, using the same paper’s nitrogen data, this would also be equivalent to reducing the nitrate content by 2.5 grams, or 10 ppm in that same 67-gal. aquarium.

 

[TWYOUNG]

Yes, these studies have been done.

Phosphate in the Reef Aquarium

The phosphorus atom is one of living matter's basic building blocks. It is present in every living creature and in every reef aquarium's water. Unfortunately, it is often present in excess in reef aquaria, and that excess has the potential to cause at least two substantial problems for...

www.reefedition.com

For those interested in knowing how much phosphorus is being exported by macroalgae, this free PDF article in the journal Marine Biology has some important information. It gives the phosphorus and nitrogen content for nine different species of macroalgae, including many that reefkeepers typically maintain. For example, Caulerpa racemosa collected off Hawaii contains about 0.08% phosphorus by dry weight and 5.6% nitrogen. Harvesting 10 grams (dry weight) of this macroalgae from an aquarium would be the equivalent of removing 24 mg of phosphate from the water column. That amount is the equivalent of reducing the phosphate concentration from 0.2 ppm to 0.1 ppm in a 67-gal. aquarium. All of the other species tested gave similar results (plus or minus a factor of two). Interestingly, using the same paper’s nitrogen data, this would also be equivalent to reducing the nitrate content by 2.5 grams, or 10 ppm in that same 67-gal. aquarium.

Excellent! Thanks so much Randy, this is exactly what I was hoping for! When you say, "dry weight', would that just mean the algae was not physically wet, or that all water was removed from its structure? I imagine my 400 gms would weigh considerably less if thoroughly dehydrated.

 

[taricha]

Excellent! Thanks so much Randy, this is exactly what I was hoping for! When you say, "dry weight', would that just mean the algae was not physically wet, or that all water was removed from its structure? I imagine my 400 gms would weigh considerably less if thoroughly dehydrated.

These are all approximations, but ballparking it, we might call chaeto 90% water weight. So if you harvest 400g patted dry with a towel, you could estimate 40g "dry weight".

 

[Randy Holmes-Farley]

Excellent! Thanks so much Randy, this is exactly what I was hoping for! When you say, "dry weight', would that just mean the algae was not physically wet, or that all water was removed from its structure? I imagine my 400 gms would weigh considerably less if thoroughly dehydrated.

As taricha indicates, it means something like oven or vacuum dried to remove most internal moisture as well.

 

[jda]

I was also just going to say that much of the algae is water.

If you freeze it for a bit, it dries out faster on it's own - I throw mine away outside since it freezes in the winter. The heaping 5 gallon buckets that I take out of my fuge are probably not 6 or 8 ounces when dry. If I remember, I can let it dry out and weigh it next time.