the active carbon debate

[Weyou]

I'm really wondering and debating whether to start using activated carbon in my aquarium. Until now I have never used active carbon but I did not really have a lot of corals but I want to hold mostly lps corals and soft corals with no sps at all. Really afraid that something will go wrong if I start using activated carbon My filtration system is based on quality rocks and quality skimmer and also water replacements with quality salt but recently want to lower the dose of water replacements. Of course I add all for reef and np bacto balance and that's it.

 

[Dan_P]

I'm really wondering and debating whether to start using activated carbon in my aquarium. Until now I have never used active carbon but I did not really have a lot of corals but I want to hold mostly lps corals and soft corals with no sps at all. Really afraid that something will go wrong if I start using activated carbon My filtration system is based on quality rocks and quality skimmer and also water replacements with quality salt but recently want to lower the dose of water replacements. Of course I add all for reef and np bacto balance and that's it.

I use GAC to remove organics that yellow the water of my fish and invert tank. I change it every 3 months because the flow through the reactor slows because of the bacteria growing on the carbon. If the level of yellow color of your water meets your expectation, don’t use GAC.

 

[Mr. Mojo Rising]

There is no need to use carbon, but nothing bad will come of it. Why do you think it will have an effect on corals? It should have no effect whatsoever if you follow the instructions.

 

[arking_mark]

My 2cents...

I used to use activated carbon as part of my regular filtration with a 6 week replacement cycle for my previous tanks and current tank.

I read a ton of varying info of the actual absorbtion lifespan of activated carbon and concluded that many of its properties are probably used up pretty quickly.

In the last year or so, I only use it for a week if I need to deal with a problem such as toxins or pollutants that may have gotten into the water or to get my water clearer...as it can yellow slightly over time.

I can honestly say that I've noticed no difference in any parameters having removed activated carbon from my now almost 2 year mature tank.

I'm guessing that younger tanks may benefit more from activated carbon...

 

[Chortanator]

Maybe it's because I used to have sea cucumbers but I like running carbon for peace of mind. If anything gets into the tank, I want it to be absorbed as quickly as possible

 

[ZombieEngineer]

I will never run a tank without activated carbon.

- Your lights are more efficient from the reduction in yellowing
- it removes some organics before they have a chance to break down.
- it removes toxic heavy metals and limits your chance of a crash from a failed magnet casing or something
- it reduces the potency of coral chemical warfare, which increases growth rates of corals that would otherwise be suppressed (ex leathers suppress other coral growth without carbon to remove toxin).

The only cons really are if you go really heavy after never using it, you can get tip burn from the increased par on your corals for a day or two. If you have tangs, unwashed or underwashed carbon is correlated with HLLE (proper washing or sediment filter solves this).

 

[Randy Holmes-Farley Verified Community Expert]

I ran GAC 24/7 and think it’s a good plan for limiting organics such as toxins and yellowing compounds.

 

[arking_mark]

I ran GAC 24/7 and think it’s a good plan for limiting organics such as toxins and yellowing compounds.

There is some evidence that GAC may only be effective for about a week to 10 days...so while effective may require frequent change.

Activated charcoal effectiveness and longevity experiment

I posted this on Facebook for my local reefing group, but I thought that it was interesting enough to share here. I recently restarted a reef tank about 7 months ago, and have been reading up on various articles on reefkeeping to try to improve my success rate with keeping fish/corals/etc as...

www.reef2reef.com

 

[Randy Holmes-Farley Verified Community Expert]

There is some evidence that GAC may only be effective for about a week to 10 days...so while effective may require frequent change.

Activated charcoal effectiveness and longevity experiment

I posted this on Facebook for my local reefing group, but I thought that it was interesting enough to share here. I recently restarted a reef tank about 7 months ago, and have been reading up on various articles on reefkeeping to try to improve my success rate with keeping fish/corals/etc as...

www.reef2reef.com

I replaced mine by swapping out about half of it every couple of weeks or so.

 

[gbru316]

I replace mine weekly, and have no compelling reason not to do so.

 

[arking_mark]

I replaced mine by swapping out about half of it every couple of weeks or so.

I use that technique for all my media (DI, Scrubber, and activated carbon when I used it) to ensure full exhaustion of media.

 

[ZombieEngineer]

I replaced mine by swapping out about half of it every couple of weeks or so.

Do you mix the new in with the old or do some sort of a FIFO setup?

 

[Randy Holmes-Farley Verified Community Expert]

Do you mix the new in with the old or do some sort of a FIFO setup?

Mixed together. I think it served as a bed for bacteria growing from vinegar dosing, and the old GAC seeded the new.

 

[polyppal]

I always run Rox in a reactor, no a ton - maybe 1/2 cup for a 70g and replace it weekly with the standard tank maintenance

carbon isn’t going to hurt anything, would only improve. I’d stay away from bituminous carbon because of the dust and mess

 

[MartinM]

I will never run a tank without activated carbon.

- Your lights are more efficient from the reduction in yellowing
- it removes some organics before they have a chance to break down.
- it removes toxic heavy metals and limits your chance of a crash from a failed magnet casing or something
- it reduces the potency of coral chemical warfare, which increases growth rates of corals that would otherwise be suppressed (ex leathers suppress other coral growth without carbon to remove toxin).

The only cons really are if you go really heavy after never using it, you can get tip burn from the increased par on your corals for a day or two. If you have tangs, unwashed or underwashed carbon is correlated with HLLE (proper washing or sediment filter solves this).

This. I see a noticeable allelopathic effect difference (even in anemones) if I don’t, as well as yellowing reduction. I change it every week.

 

[las]

Carbon is mandatory in any setup of mine.

 

[landlubber]

the only downside to gac I've ever really heard of was it may contribute to HLLE in tangs. that being said, I've been running it in my system for the past 7 years and haven't had that or any other issues.

 

[ReefGeezer]

I use it passively. I have two filter bags that sit in the sump where the water overflows into the return area. I alternate replacing them but don't replace them often. I think the bags get coated with organics and do little good eventually so I do rinse each one occasionally... but not as much as I should.

 

[mje113]

What does the "G" stand for in "GAC"?

 

[Randy Holmes-Farley Verified Community Expert]

What does the "G" stand for in "GAC"?

Granular