Do you use activated carbon at all times, intermittently or never?

[TokenReefer]

This is pretty much my experience also. I have always been curious about carbon though - I wonder if the folks that run it 24/7 do so for a specific reason? What happens if you stop running it or forget to change it out?

Aren't the benefits well documented? I doubt it'd be harmful to stop using it though, whether changes are perceived or not

 

[Spare time]

I was running in a reactor 24/7, moved to passively in a bag, and now do not run it at all. I have noticed zero change in my water quality.

You can't see many of the things carbon removes

 

[SpyC]

You can't see many of the things carbon removes

You can see changes in water clarity and if livestock is 'acting' differently between running vs not running carbon.

 

[DanyL]

24/7 in 2 systems.

Most of my reefing years I’ve been using it in a bag, last 3 or so years I’ve been using a reactor which makes it last longer for me.

I change it approximately every 1 to 2 months, when I notice my water is getting slightly yellowed when I look at the tank from the side with lights off.

I never had a concern it’d deplete elements because even if it does it would be in such small amounts that it would either not bother corals at small consumption or would be a really small percentage in uptake in a high demanding system where you replenish it anyways.
I’m leaning more to the later, and I rarely see any deficiencies in my ICP tests with daily dosing and weekly WC with real seawater.

 

[FrugalReefer]

Removed my GAC in September and haven’t used it since. I know there are reefers who use it with great success and more power to them, but for me, when I use it my SPS get P.O.ed to the point they eventually STN.

 

[TWYOUNG]

My ORP stays between 220-250 if my probe is accurate. It doesn’t spike with ozone usage which runs for 6 hours every night

I know value of tracking ORP is debatable but that seems very low for a tank with ozone. Mine runs 300-350 without it.

 

[TWYOUNG]

24/7 in 2 systems.

Most of my reefing years I’ve been using it in a bag, last 3 or so years I’ve been using a reactor which makes it last longer for me.

I change it approximately every 1 to 2 months, when I notice my water is getting slightly yellowed when I look at the tank from the side with lights off.

I never had a concern it’d deplete elements because even if it does it would be in such small amounts that it would either not bother corals at small consumption or would be a really small percentage in uptake in a high demanding system where you replenish it anyways.
I’m leaning more to the later, and I rarely see any deficiencies in my ICP tests with daily dosing and weekly WC with real seawater.

That's one point I considered mentioning initially but didn't want the post to get too long. There has never been a hint of yellow to my water even during the first year when I wasn't using carbon and rarely did water changes due to low nutrient levels.

 

[DanyL]

That's one point I considered mentioning initially but didn't want the post to get too long. There has never been a hint of yellow to my water even during the first year when I wasn't using carbon and rarely did water changes due to low nutrient levels.

It could very possibly be stemmed by the early age of your system, or you simply didn’t notice the very slight tint because it does need some practice to be able to spot it the first few times, at least without filling a white bucket with water from the tank where it is more noticeable.

For me, my very first system started out with real live rocks, and been upgraded ever since - so I never really experienced a freshly cycled tank to compare.

Carbon still does have the ability to remove toxins and other unmeasurable things from the water even if clarity isn’t an issue - but I don’t know how you would tell wether it needs to be replaced or not without being able to do the water clarity test.

Edit: I’ve seen now that you’re using ozone. That explains everything tbh.

 

[Toob]

Aren't the benefits well documented? I doubt it'd be harmful to stop using it though, whether changes are perceived or not

Are they? Can you share links to those documents?

 

[fishface NJ]

I don't use it.

 

[MartinM]

I’m not convinced does anything beneficial that I need. Water clarity? Ozone and Coral Snow. Odors? Ozone. Toxins? Ozone.

You’re using ozone without carbon? I thought Randy said the effluent water will have lots of harmful bromides (or was it bromines) if it wasn’t passed over carbon after being ozonized but I could be wrong.

I think Randy also demonstrated the clearest water was achieved with Ozone and carbon. I run both (and UV, actually a catalytic UV for even more clarity).

I notice clearly detrimental responses with my carpet anemones when I don’t run it or let it go too long without changing it. Probably some allelopathy but who knows for sure.

 

[Reef By Steele]

I will have to say that I used it when I started in the 80’s. Was told to run it all the time and change it monthly. When I got back into the hobby, I was told by the LFS that I didn’t need to run it, but old dogs new tricks, so I bought it and added it.

Sometimes I forget I have it in the sump as I run bags of biomedia (Seachem Matrix) for use to start new tanks etc.

But I realize now that in my 210 reef I wasn’t running it. Months ago before my surgeries I was dragging a bunch of stuff including palys. Shortly after I did this I lost almost all my corals in the tank. It was truly heartbreaking and I had no clue why.

Just recently I cleaned up my 3XL900 that has been fallow for months, and neglected as I couldn’t do anything during my recovery. While scrubbing bubble algae off the rocks I scrubbed some palys. I ended up with either palytoxin or another infection, and the anthelia and Xenia in the tank really took a hit. I added carbon to the tank and everything has settled down a lot.

I now believe it is something that should be run IMO. I think it is a good safe guard and the benefits out way the risks.

 

[TokenReefer]

Are they? Can you share links to those documents?

Sure...from an off the cuff, two second Google....Anecdotal, maybe but documented

The Role of Activated Carbon in the Reef Aquarium | Reef Builders | The Reef and Saltwater Aquarium Blog

Of the three types of filtration used in the reef aquarium hobby today, biological, mechanical, and chemical, it is chemical filtration that is possibly the least understood. This post is all about…

reefbuilders.com

Activated Carbon for Reef Tanks - Bulk Reef Supply

Bulk Reef Supply - Saltwater Aquarium Supplies for Reef Tanks

www.bulkreefsupply.com

Carbon In The Reef Tank - Part 1 (Repost) | Melev's Reef

melevsreef.com

Btw the last one looks particularly interesting, haven't read it yet, going back to it. Not sure if you were trying to just call me out but I'm sure you can google up the rest of the stuff that's out there...and try to debate it.... I guess

 

[Js.Aqua.Project]

If you are genuinely curious about the ozone byproducts @Js.Aqua.Project mentioned, Randy has an article about it.

https://reefkeeping.com/issues/2006-03/rhf/index.php#15

I understand you said your tank is doing fine without the carbon. I’m not implying you need to start adding carbon. I am a believer in doing things that work for you.

In my tank, the ORP rises much higher, so I personally use carbon.

@Miami Reef beat me to it but the article he mentions here by @Randy Holmes-Farley was what I was going to search for to show you. Randy has (I think) a 3 part series on ozone and its impact on the reef aquarium.

 

[Randy Holmes-Farley]

How often do you believe it needs to be changed? I'm using about a cup at a time of 0.8 ROX per 130 gals in a reactor.

The answer will depend on many factors including the degree of organics added to the water and how fast bacteria multiply on it.

I replaced half of it every couple of weeks. I used in a forced flow reactor.

 

[Toob]

Sure...from an off the cuff, two second Google....Anecdotal, maybe but documented

The Role of Activated Carbon in the Reef Aquarium | Reef Builders | The Reef and Saltwater Aquarium Blog

Of the three types of filtration used in the reef aquarium hobby today, biological, mechanical, and chemical, it is chemical filtration that is possibly the least understood. This post is all about…

reefbuilders.com

Activated Carbon for Reef Tanks - Bulk Reef Supply

Bulk Reef Supply - Saltwater Aquarium Supplies for Reef Tanks

www.bulkreefsupply.com

Carbon In The Reef Tank - Part 1 (Repost) | Melev's Reef

melevsreef.com

Btw the last one looks particularly interesting, haven't read it yet, going back to it. Not sure if you were trying to just call me out but I'm sure you can google up the rest of the stuff that's out there...and try to debate it.... I guess

Not trying to call you out - I’m sincerely looking for quality documentation.

I believe it probably removes smells and yellowing (since carbon does that everywhere outside the hobby), but if your water isn’t yellow or smelly why run it? Especially why run it 24/7?

I’m not looking for brief reef builders articles or BRS advertisements - lol. I respect reef builders but all theirs says is smells and water clarity - which again, is fine, but that’s it?

Looking for actual scientific papers or at least some fairly rigorous anecdotes and/or testing by well known hobbyists. The Melev article is a great example of this - but yet again, it’s all about simply removing yellow tint from the water. Which is great, perhaps that is all that carbon does - I’ll use it if my water turns yellow, but otherwise…why?

 

[Randy Holmes-Farley]

That's one point I considered mentioning initially but didn't want the post to get too long. There has never been a hint of yellow to my water even during the first year when I wasn't using carbon and rarely did water changes due to low nutrient levels.

Many people say that. Then they use GAC, or even more so ozone, and even spouses comment on the change.

 

[Randy Holmes-Farley]

Not trying to call you out - I’m sincerely looking for quality documentation.

I believe it probably removes smells and yellowing (since carbon does that everywhere outside the hobby), but if your water isn’t yellow or smelly why run it? Especially why run it 24/7?

I’m not looking for brief reef builders articles or BRS advertisements - lol. I respect reef builders but all theirs says is smells and water clarity - which again, is fine, but that’s it?

Looking for actual scientific papers or at least some fairly rigorous anecdotes and/or testing by well known hobbyists. The Melev article is a great example of this - but yet again, it’s all about simply removing yellow tint from the water. Which is great, perhaps that is all that carbon does - I’ll use it if my water turns yellow, but otherwise…why?

Granular Activated Carbon, Part 1: Modeling of Operational Parameters for Dissolved Organic Carbon Removal from Marine Aquaria

Chemistry Department, The Pennsylvania State University. In this first part of a two part series, the authors will introduce granular activated carbon and explain the experimental goals and mathematical models used in their research.

reefs.com

Bacterial Counts in Reef Aquarium Water: Baseline Values and Modulation by Carbon Dosing, Protein Skimming, and Granular Activated Carbon Filtration

What are the bacteria populations in the water column of reef tanks, and how does that value compare with bacterial counts in authentic reef water? Does carbon dosing indeed increase water column bacteria populations (i.e., is growth carbon limited)? Does mechanical filtration (protein skimming...

reefs.com

Granular Activated Carbon, Part 2: Modeling of Operational Parameters for Dissolved Organic Carbon Removal from Marine Aquaria

Chemistry Department, The Pennsylvania State University. In Part 2, the authors will discuss the results of their research and make some recommendations to the aquarist on its usage.

reefs.com

 

[TokenReefer]

The reason I 'run' it 24/7 is because I have big mushrooms and a couple anenomes and early on in my reefing knowledge gathering I read about GAC and how it can help remove some of the toxins produced by those creatures, as well as help clear the water. I'm not a scientist and have no leg to stand on to debate after reading a lot on it (back then) so I decided to add it. After reading about HLLE (again not a scientist so erred on the side of caution), I decided I'd use it sort of passively in a filter cup in my sump instead of a sock (I don't run socks in the other slots) and let it run 24/7 since not all the water goes through it, eventually it will...that was my train of thought a while back and have just stuck with it because I do have crystal clear water. If that changes I may re-assess.

I didn't mean to get into this whole thing btw; just wanted to say removing something doesn't have to mean there's a negative, but adding something can add benefits. Actually, there are so many variables in a reef tank it's almost impossible to say (imo) if my last statement is always true as there can I suppose be a negative if removed if it was doing a job of removing toxins, etc. Sorry, I can't always see all the ends

 

[Toob]

Granular Activated Carbon, Part 1: Modeling of Operational Parameters for Dissolved Organic Carbon Removal from Marine Aquaria

Chemistry Department, The Pennsylvania State University. In this first part of a two part series, the authors will introduce granular activated carbon and explain the experimental goals and mathematical models used in their research.

reefs.com

Bacterial Counts in Reef Aquarium Water: Baseline Values and Modulation by Carbon Dosing, Protein Skimming, and Granular Activated Carbon Filtration

What are the bacteria populations in the water column of reef tanks, and how does that value compare with bacterial counts in authentic reef water? Does carbon dosing indeed increase water column bacteria populations (i.e., is growth carbon limited)? Does mechanical filtration (protein skimming...

reefs.com

Granular Activated Carbon, Part 2: Modeling of Operational Parameters for Dissolved Organic Carbon Removal from Marine Aquaria

Chemistry Department, The Pennsylvania State University. In Part 2, the authors will discuss the results of their research and make some recommendations to the aquarist on its usage.

reefs.com

Thanks Randy, I was hoping you would chime in. I have read the Feldman articles and find them quite good. However, my takeaway was that

1. Hobbyists can’t really measure DOC so we don’t know how much is in our tanks and

2. Even if we could, we don’t know what levels of DOC are optimal since there are examples of thriving tanks at various levels.

Total Organic Carbon (TOC) and the Reef Aquarium: an Initial Survey, Part II

Department of Chemistry, The Pennsylvania State University, University Park, PA 16802. Ken and Kelly continue to report on their work on Total Organic Carbon and how it relates to the reef aquarium.

reefs.com

So why add GAC to a tank to reduce DOC if you don’t know what level your DOC are or even what they should be?