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Manchestercity
09-19-2014, 01:28 PM
So I just an article online that stated activated carbon removes compounds that help create that thick foam we all love seeing are protein skimmer produce. Has anyone heard or experienced carbon having any effect on their skimmers performance?

kutcha
09-19-2014, 01:51 PM
article link?

Manchestercity
09-19-2014, 02:01 PM
Yeah here's the link. It's a long article so I just copied the paragraph

http://www.aquarium-pond-answers.com/2009/10/activated-carbon.html?m=1


The use of Activated Carbon with Marine Protein Skimmers:

Although conclusive tests are forth coming, there is evidence that the use of activated carbon can limit the amount of foam refraction generated by a marine protein skimmer. This is likely due to the adsorption of Foaming Agents (MBAS) by activated carbon.
This presents a problem for many reef keepers since both carbon and protein skimmers are useful aspects of a complete marine filtration system.
My suggestion is to limit carbon use in cleaning filters run during certain times of the day (or week), especially after heavy feeding.

Just_Tim
09-19-2014, 05:29 PM
Huh. I've been wondering why my skimate thinned out. I started carbon use last week and well, dang.


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Balz3352
09-19-2014, 05:42 PM
Interesting... I was wondering the same thing... Switched from brs regular to rox because it was given to me my skimmate completely changed.... I wonder if I could use thickening skimmate to tell me I need new carbon

Just_Tim
09-19-2014, 06:32 PM
Interesting... I was wondering the same thing... Switched from brs regular to rox because it was given to me my skimmate completely changed.... I wonder if I could use thickening skimmate to tell me I need new carbon

Great idea. I was thinking that pulling skimable waste from the water before the skimmer can't be that bad. It's still pulling waste.


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Manchestercity
09-19-2014, 08:03 PM
Great idea. I was thinking that pulling skimable waste from the water before the skimmer can't be that bad. It's still pulling waste.


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I don't know if that's the case here. The waste that builds up in filter carbon becomes a nitrate factory and is still in the water column. A skimmer on the other hand removes the waste from the water column.

Just_Tim
09-19-2014, 08:49 PM
Good point. What is the proper way to rinse carbon. The chemical filtration I'm using is a mechanical carbon pad. It takes the place of a floss pad. It's still new but I was rinsing my floss weekly. Would rinsing in the same manner wash away enough detritus to make this work?


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Murfman
09-19-2014, 10:50 PM
Carbon is good at removing yellow water and some stuff for about 3 weeks to a month and then becomes a nitrate trap. If you are OK with your water clarity, then forgo the carbon, unless you need to do the additional clearing of your water.

static reef
09-19-2014, 10:51 PM
Carbon is good at removing yellow water and some stuff for about 3 weeks to a month and then becomes a nitrate trap. If you are OK with your water clarity, then forgo the carbon, unless you need to do the additional clearing of your water.

Well said. I dont run it as I think it is an extra expense for little reward. If your water is yellow change out your water and turn your skimmer to run a little more wet.

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scrumpto
09-20-2014, 02:07 AM
Good point. What is the proper way to rinse carbon. The chemical filtration I'm using is a mechanical carbon pad. It takes the place of a floss pad. It's still new but I was rinsing my floss weekly. Would rinsing in the same manner wash away enough detritus to make this work?

Probably better to use standard filter floss which can be more easily rinsed out and then carbon which can be thrown away when exhausted.

On granular activated carbon (GAC) being a nitrate factory, this is possible. However, it was suggested years ago that the deep pores of carbon are potentially a better zone for denitrification than the pores of live rock. So once the GAC pores are full of junk -- in theory anaerobic bacteria would in these pores perform denitrification the same as any other media such as ceramic rings only better.

This wasn't the original source of the information but here's one citation:
http://books.google.com/books?id=WYP5k7xGCxgC&pg=PA19&lpg=PA19&dq=reef+activated+carbon+anaerobic+pores+denitrifi cation&source=bl&ots=-dasz8jfMp&sig=hbt09XCdGAh9c0E9vXkBXD4tl2E&hl=en&sa=X&ei=pC4dVIrMBNCUyATJ_4GICA&ved=0CCMQ6AEwAA#v=onepage&q=reef%20activated%20carbon%20anaerobic%20pores%20 denitrification&f=false

Based on other reading I've done regarding GAC and fresh water filtration nitrate can build up in carbon and be released suddenly so both are possible situations it would seem.

With regard to protein skimmers, in the study done in 2010
http://www.advancedaquarist.com/2010/1/aafeature
They found the following with regard to the ability of skimmers to remove total organic carbon (TOC):
"A perhaps more interesting observation to emerge from these skimmer studies involves not the rate of TOC removal, but rather the amount of TOC removed. None of the skimmers tested removed more than 35% of the extant TOC, leading to the conclusion that bubbles are really not a very effective medium for organic nutrient removal."

So if a protein skimmer only has the ability to remove at most 35% of the TOC in a tank then I see GAC as a method of removing more. Here's what one of the authors said in the comments following the above article:
"In some as yet unpublished work, we have shown that GAC is very effective at stripping aquarium water of its TOC load; from 60 - 90% removal, if I recall correctly, depending on specifics. We looked at ROX, HC2 and Black Diamond GAC's. The ROX was the winner by far."

Ideally, I would run a skimmer 24/7, remove 50% of the water during a water change and run it through GAC and a number of other filter resins and then replace the 50% water with new salt water during a water change. Then again, water and salt might be less expensive than GAC so maybe you just do larger more frequent water changes to remove TOC. The article does suggest that regular water changes are not only important as TOC continues to rise even with filtration but that they can be a substitute for skimmers and other filter media (obviously). In this we see that filters and filter media simply slow down the need for water changes.

That said and before anyone starts a war, there are systems which have not done water changes in years which are completely stable and healthy. I cannot imagine how green the water is though -- maybe as green as the glass itself. Maybe blue lights alleviate this ;-)

With regard to GAC removing foaming agents from the water which affects the skimmer, this may be entirely true. Another interesting conclusion is that the GAC is performing the same task as the skimmer only better. Hence the skimmer has less TOC to remove and thus less foam.

For what it's worth...

NightStar
09-20-2014, 10:18 AM
Good point. What is the proper way to rinse carbon. The chemical filtration I'm using is a mechanical carbon pad. It takes the place of a floss pad. It's still new but I was rinsing my floss weekly. Would rinsing in the same manner wash away enough detritus to make this work?


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If I remember correctly, you're running carbon to combat chemical warfare between your corals. It does work for that, and is one of the reasons I keep it around in case of emergencies. Given the other issues with carbon though, I highly recommend polyfilter instead. With a fully cycled tank, as you know, it's not needed for the actual filtration purposes, just the polishing and chemical removal. Polyfilter will remove chemicals more efficiently and (and this is a big and) will remove iron and other heavy metals that carbon will not. I do run the polyfilter in my sumps as close to the return pump as I can. Mostly because I'm cheap and skimmers and bio filters in a sump are free and the less it has to filter the longer it will last.

Just_Tim
09-20-2014, 10:29 AM
Ahh yes. The chemical warfare :). I gave up chemical filtration long ago with freshwater. But then again plants don't outright try to kill their neighbors. I must say that since I've added the chems my junk looks better than it ever has. I should probably come up with a schedule. I.e; week on week off with the carbon pads.


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