Carbon. , Phosphates

rich19020 · 05/29/2012, 08:36 PM

Today at the LFS I was told not to run carbon because it can leak phosphtes. Is that true?

fishchef · 05/29/2012, 09:17 PM

Carbon tends to release absorbed compounds once its exhausted which would include PO4. It needs to be replaced often and a high grade should be used. We stopped using carbon years ago. We like a combination of Purigen and Polyfilter with a GFO reactor on the system.

tmz · 05/29/2012, 09:46 PM

A little perhaps depending on how it was made( if washed with phosphoric acid for example) but it takes up organics that hold some phosphate so the overal effect should be less not more phosphate. Rox 8 is a good bet not to contribute PO4. I use it 24/7 and replace it monthly. PO4 is low in my system but I also dose vodka and vinegar and run a little gfo.

I don't think purigen is immune from exhaustion and leaching but it's a nice product. I've run both gac and purigen on the speculative hope they have an affinity for different organics and both be more effective than one or the other in removing organics overall. I do keep poly pad going as a preventative for any free metals that may show up along with a bag of cupramine.

Buzz1329 · 05/29/2012, 10:10 PM

Quote:

Originally Posted by fishchef

Carbon tends to release absorbed compounds once its exhausted which would include PO4. It needs to be replaced often and a high grade should be used. We stopped using carbon years ago. We like a combination of Purigen and Polyfilter with a GFO reactor on the system.

Do we?

Randy Holmes-Farley · 05/30/2012, 04:44 AM

The carbon leaking phosphate has been a worry for some because some forms do come with a little phosphate on them. But in general, and good hobby brand (like BRS ROX or Seachem Matrix) will not leach enough to be significant relative to the phosphate in the foods you add daily.

I discuss that here:

Phosphate and Food
http://www.advancedaquarist.com/2012/3/chemistry

from it:

The same sort of calculation applies to analyzing other phosphate issues, such as the GAC in scenario three. The issue of finding "high" phosphate in GAC soaked in fresh water was frequently quoted as a reason to use one or the other brand of GAC, and probably still is. But simple analysis as shown above for the food rinsing puts the lie to this being a big problem.

One needs to consider how much GAC one will really use in the aquarium and how often it is added in order to interpret how important the added phosphate is. A typical recommendation might be 1 cup of GAC per 100 gallons of aquarium water, and to change it in 4-6 weeks. Let's assume we detect 0.5 ppm phosphate when a teaspoon is placed in a cup of water, and we get scared by the dark blue color during the test. Is this reasonable? That 0.5 ppm from a teaspoon in a cup of water translates to 0.015 ppm phosphate when a cup is used in 100 gallons.

That 0.015 ppm may be significant, being a typical target concentration level for reef aquaria and amounting to about half to a twentieth of the amount added daily in foods, but remember, it is used for 4-6 weeks. During those 4-6 weeks before the next replacement, foods add 50-700 times as much phosphate. So while it is not unreasonable to look for another brand of GAC, to blame phosphate or algae issues in the aquarium on its use would stretch credibility because it is a very tiny portion of the total phosphate being added.

shiladitya1991 · 05/30/2012, 06:30 AM

I put my activated carbon in a canister filter(Eheim 2217) and fill it up with boiling RO water. Let it sit for 12hours. A layer of organic is deposited on the surface. Rinse the carbon with some fresh RO water and its ready to use...

Buzz1329 · 05/30/2012, 08:36 PM

Quote:

Originally Posted by shiladitya1991

I put my activated carbon in a canister filter(Eheim 2217) and fill it up with boiling RO water. Let it sit for 12hours. A layer of organic is deposited on the surface. Rinse the carbon with some fresh RO water and its ready to use...

Wait a minute! Everyone knows that the boiling RO water has to sit for 12.67 hours for this to work. Am I right? Or what?

shiladitya1991 · 05/30/2012, 10:29 PM

Yeah you are

Well Allmost told me this,works nice...

rich19020 · 06/01/2012, 02:19 PM

Thanks everybody for your input.

05/29/2012, 08:36 PM	#1
rich19020 Registered Member Join Date: Jun 2011 Location: Yardley, PA Posts: 389	Carbon. , Phosphates Today at the LFS I was told not to run carbon because it can leak phosphtes. Is that true?

05/29/2012, 09:46 PM	#3
tmz ReefKeeping Mag staff Join Date: Apr 2006 Location: West Seneca NY Posts: 27,691	A little perhaps depending on how it was made( if washed with phosphoric acid for example) but it takes up organics that hold some phosphate so the overal effect should be less not more phosphate. Rox 8 is a good bet not to contribute PO4. I use it 24/7 and replace it monthly. PO4 is low in my system but I also dose vodka and vinegar and run a little gfo. I don't think purigen is immune from exhaustion and leaching but it's a nice product. I've run both gac and purigen on the speculative hope they have an affinity for different organics and both be more effective than one or the other in removing organics overall. I do keep poly pad going as a preventative for any free metals that may show up along with a bag of cupramine. __________________ Tom Current Tank Info: Tank of the Month , November 2011 : 600gal integrated system: 3 display tanks (120 g, 90g, 89g),several frag/grow out tanks, macroalgae refugia, cryptic zones. 40+ fish, seahorses, sps,lps,leathers, zoanthidae and non photosynthetic corals.

05/30/2012, 04:44 AM	#5
Randy Holmes-Farley Reef Chemist Join Date: Apr 2001 Location: Arlington, Massachusetts Posts: 86,233	The carbon leaking phosphate has been a worry for some because some forms do come with a little phosphate on them. But in general, and good hobby brand (like BRS ROX or Seachem Matrix) will not leach enough to be significant relative to the phosphate in the foods you add daily. I discuss that here: Phosphate and Food http://www.advancedaquarist.com/2012/3/chemistry from it: The same sort of calculation applies to analyzing other phosphate issues, such as the GAC in scenario three. The issue of finding "high" phosphate in GAC soaked in fresh water was frequently quoted as a reason to use one or the other brand of GAC, and probably still is. But simple analysis as shown above for the food rinsing puts the lie to this being a big problem. One needs to consider how much GAC one will really use in the aquarium and how often it is added in order to interpret how important the added phosphate is. A typical recommendation might be 1 cup of GAC per 100 gallons of aquarium water, and to change it in 4-6 weeks. Let's assume we detect 0.5 ppm phosphate when a teaspoon is placed in a cup of water, and we get scared by the dark blue color during the test. Is this reasonable? That 0.5 ppm from a teaspoon in a cup of water translates to 0.015 ppm phosphate when a cup is used in 100 gallons. That 0.015 ppm may be significant, being a typical target concentration level for reef aquaria and amounting to about half to a twentieth of the amount added daily in foods, but remember, it is used for 4-6 weeks. During those 4-6 weeks before the next replacement, foods add 50-700 times as much phosphate. So while it is not unreasonable to look for another brand of GAC, to blame phosphate or algae issues in the aquarium on its use would stretch credibility because it is a very tiny portion of the total phosphate being added. __________________ Randy Holmes-Farley Current Tank Info: 120 mixed reef

05/29/2012, 09:17 PM	#2
fishchef Registered Member Join Date: Feb 2009 Location: St. Louis, MO Posts: 1,222	Carbon tends to release absorbed compounds once its exhausted which would include PO4. It needs to be replaced often and a high grade should be used. We stopped using carbon years ago. We like a combination of Purigen and Polyfilter with a GFO reactor on the system.

05/30/2012, 06:30 AM	#6
shiladitya1991 Registered Member Join Date: Sep 2009 Location: India Posts: 376	I put my activated carbon in a canister filter(Eheim 2217) and fill it up with boiling RO water. Let it sit for 12hours. A layer of organic is deposited on the surface. Rinse the carbon with some fresh RO water and its ready to use...

05/30/2012, 10:29 PM	#8
shiladitya1991 Registered Member Join Date: Sep 2009 Location: India Posts: 376	Yeah you are Well Allmost told me this,works nice...

06/01/2012, 02:19 PM	#9
rich19020 Registered Member Join Date: Jun 2011 Location: Yardley, PA Posts: 389	Thanks everybody for your input.