What Are The Effects Of Adding Carbon?

[fifefish]

i have a bag of carbon and a filter bag to put it in do you think i should put it in my filter or should i not bother..what are the effects of carbon to my tank?

 

[fishdaddy]

Do you mean activated carbon Filter media??

If so then do use it !!

I always use it. It makes the water crystal clear. Looks lovely. Change it once a month

cheers

 

[Bignose]

Carbon is fairly unnecessary in my opinion, and even takes away some potentially valuable chemicals in the tank.

First of all, carbon is only truly useful for about a day or two. After that, it has become saturated and really doesn't take up much more. In fact, the bonds between what is adsorbed by the carbon and the carbon itself are reversible, and the potential exists for the adsorbants to be releases back into the tank. So, to really get get the most out of carbon, you have to change it every few days or so.

Secondly, carbon does adsorb a class of compounds called DOCs (dissolved organic compounds, tannins is a very good example). DOCs can actually be quite useful in a fish tank -- DOCs bind to heavy metals, making the heavy metals much less toxic than in their original form. If the carbon is taking away those DOCs, then the metals could be free in your tank. Part of this issue is that the levels of metal toxicity in water for humans can be as much as 1000 times higher than the level of metal toxicity for fish. I.e. copper is not toxic to humans until well back the concentration where the average person can taste copper in the water. But, at that point, the concentration of copper is already many, many times the level of toxicity for a lot of fish. The water companies aren't regulating their water to be safe for fish, they are regulating their water to be safe for humans. If your tank has DOCs in it (some come from the fish themselves, more come from live plants if you have them), the DOCs can bind with copper making the copper much less toxic.

Many water conditioners do bind up with heavy metals, too. But, there is this extra level of protection that activated carbon will take from the water. I think it is a good idea to leave that extra level of protection alone.

I personally only use carbon after a course of medications. The carbon is very good about getting medications out of the water. Then, I throw the carbon away (again, it can release chemicals back into the tank!). And, I too have crystal clear water. Good maintenance and water changes accomplish that more than anything. Carbon is just something extra the manufacturers want you to buy once a week or once a month. It isn't necessary, and has limited benefits in my opinion.

 

[LauraFrog]

I use it only because of periodical contamination of my water supply with fertiliser and pesticide runoff. Every time this happens I get no warning and I lose fish. Because I don't need the carbon to remove anything in particular I leave it there for months - and when I water change the snail tank and they all drop dead, I know there's runoff in the water supply and start changing all the carbon in my filters daily.

 

[dcarmor927]

Using the carbon will help get rid of heavy metals in the water, Bignose gives the science for you, and it will also help if you've given medication to your fish

 

[andywg]

Using the carbon will help get rid of heavy metals in the water, Bignose gives the science for you, and it will also help if you've given medication to your fish

If you read what bignose has posted he actually points out that the carbon will adsorb DOC which themselves bind to heavy metals. Having carbon in the tank would therefore increase the risk of heavy metals being a problem.

 

[Bignose]

Using the carbon will help get rid of heavy metals in the water, Bignose gives the science for you, and it will also help if you've given medication to your fish

What Andy said. Carbon actually doesn't bind too well to heavy metals. Most metals are found in ionic forms in the water. Activated carbon doesn't usually participate in ionic bonding. Activated carbon is usually participating in covalent bonding. This is the reason is it usually good at adsorbing organic compounds (which have lots of carbons in their structures and easily bind with other carbons), and nitrogen compounds. And metals don't often participate in covalent bonding. So, activated carbon actually doesn't do a very good job of taking up metals, but bonds to the compounds that would otherwise pick up those metals.

 

[jnms]

I use activated carbon to remove tannins from my tank - which gets a little like tea.

I don't overly like using the carbon, so is there anything else I can do? Aside from soaking the bogwood again?

 

[dcarmor927]

my bad i guess i read it wrong, thanks for the correction

 

[JakeKM]

Activated Carbon plays quite an import part in the marine tank does it not ? Removing all kinds of toxins produced by corals and also marine animals are more senstative to DOC's than their fresh water counterparts.