Should I run Carbon?

[MadTownFess]

It is important to understand that carbon is only good for 3-5 days and then must be changed out or it will leach everything it has sucked up, back into the water.

I run it through a reactor as that is the most effective way to run carbon. And not all carbon is created equal so make sure you get a high grade activated carbon. I personally would not run a tank without it and my corals are as healthy as can be with amazing growth.

If you are going to run it passively then I would recommend Chemi-Pure Blue.

Would you like to share your research/source for claiming carbon will leach everything back in the water? Many sources say that is not the case:

"You may have heard that once activated carbon has reached its capacity, it will start leaching some absorbed materialsback into the water. This is not an accurate claim. Although technically possible, de-absorbing requires changes in waterchemistry that simply do not occur in an aquarium "

 

[Saltyanimals]

+ 1 on the interest there on leaching back.

One of the reason's I don't do GAC often so because I always forget to change. Case in point, I just changed my carbon (passive) 10 mins earlier. Immediately looking back at my Apex maintenance log, I see that I last changed it over 3 months ago. I know I know. bad reef keeper! But let that be an example of where I never noticed any thing significant negative in the tank. Running 65 G - SPS / mixed reef with large colonies. I sometimes ask myself why I would even run carbon anymore except as-needed when I need to remove toxins. I'm aware of all the benefits of it such as clearer water, but just haven't experienced anything that serves as a reminder to change / run GAC.

I'll do better going forward.. shoot for monthly change. =) But curious to hear the leaching research as I just threw out a 3+ month old carbon bag.

 

[Slawman]

I have run carbon on and off over the years. It is effective at pulling a lot of toxic stuff out of the water and it helps to polish it giving you something sparkling clear however I do not run it now and have not for a few years. Mainly because I got sick of maintaining it and buying it. Don't notice much difference on my setups. I keep it on hand in case I need to use it though.

 

[Randy Holmes-Farley Verified Community Expert]

Carbon will not leach anything back into the water unless something else that it binds more strongly to the same site displaces it, or the thing that bound is now much lower in concentration in the water so an equilibrium on/off situation drives some off.

In either case, there is little reason to think this is an important reason to use it or not use it (Unless, perhaps, you used it to bind and remove a medication).

How fast it is depleted depends entirely on the organic levels (and types) in the water. I’d replace it after 2-4 weeks unless the water is yellowed, or in a problem situation in which case faster might be useful.

 

[vetteguy53081]

Running a mixed reef, i run carbon mainly to reduce toxins from softies that can affect SPS. The inly reason other than polishing water

 

[Saltyanimals]

Carbon will not leach anything back into the water unless something else that it binds more strongly to the same site displaces it, or the thing that bound is now much lower in concentration in the water so an equilibrium on/off situation drives some off.

In either case, there is little reason to think this is an important reason to use it or not use it (Unless, perhaps, you used it to bind and remove a medication).

How fast it is depleted depends entirely on the organic levels (and types) in the water. I’d replace it after 2-4 weeks unless the water is yellowed, or in a problem situation in which case faster might be useful.

Thanks, Randy. That's a sound argument and perhaps why my tank hasn't crashed for the 3 month old GAC. =) The 2-4 is more frequently than the previous monthly change I've heard, but again makes sense when consider the organic levels and how much it is "used" in a particular tank.

I've always considered myself having a successful tank, but maybe I've limited it the whole time because of my GAC habits. Will give more frequent GAC habit a try.

 

[Wee Mad Arthur]

Having just upgraded I was debating whether to run carbon on this tank and decided to try without. I recently watched a YouTube video claiming that the chemicals released by soft corals were over hyped and that they only tended to release when touching each other, I don’t know how much truth is in that but unless you’ve tried with and without carbon you can’t really be sure of its impact. There is also the unknown as to how long the carbon lasts for. If indeed it’s only good for a few days then changing it weekly or monthly is pointless as the benefit was extremely short lived. How many people are changing it after only a few days?

 

[vetteguy53081]

ChemiPure Blue here. 9-12 weeks before change

 

[sawdonkey]

I run it now and then. I just put it in a mesh bag and throw it on the end of one of my return pipes. I only run it if my water is looking yellow and only for a couple days. I suspect it does something my coral doesn’t like as I’ve noticed my corals not looking as happy when I run it...and I could just be crazy. I have absolutely no proof, but this is my reason for not running it.

 

[pixter]

+ 1 on the interest there on leaching back.

One of the reason's I don't do GAC often so because I always forget to change. Case in point, I just changed my carbon (passive) 10 mins earlier. Immediately looking back at my Apex maintenance log, I see that I last changed it over 3 months ago. I know I know. bad reef keeper! But let that be an example of where I never noticed any thing significant negative in the tank. Running 65 G - SPS / mixed reef with large colonies. I sometimes ask myself why I would even run carbon anymore except as-needed when I need to remove toxins. I'm aware of all the benefits of it such as clearer water, but just haven't experienced anything that serves as a reminder to change / run GAC.

I'll do better going forward.. shoot for monthly change. =) But curious to hear the leaching research as I just threw out a 3+ month old carbon bag.

My carbon bags stay in at least 6 months or more. I had no idea they turned bad. I never experience anything negative with it and I don’t ever hear anything about it.

 

[Stephen Glover]

l run carbon when I notice a yellow tint in my white bucket when doing a water change. Run it for a week about every month or so.

 

[Randy Holmes-Farley Verified Community Expert]

My carbon bags stay in at least 6 months or more. I had no idea they turned bad. I never experience anything negative with it and I don’t ever hear anything about it.

You don’t hear anything about what, exactly?

 

[jda]

Old carbon just turns into an aerobic filter. It won't hurt anything. Once it gets coated in organics, there are a few studies that show that water does not really penetrate the film for stuff to either get bound or unbound. This can happen in as little as 7-10 days if left undistrubed in a passive bag but does not happen for much longer in a reactor or with faster water flow.