Something on Carbon

[astha2]

I found this useful reading on indodragon website on Carbon. Hope it's something helpful for everyone.

The original link is here
http://www.indodragon.com/forum/show...hing-on-Carbon

The content:

Carbon is a wonderful product and there are basically 2 types. Carbon n activated carbon. Carbon comes from many products like wood, coconut shell, bitumen, coal, etc. .The term activated refers to carbon that has been subjected to very high pressures and temperatures to drive out all impurities and gases, leaving behind extremely porous and pure grains of carbon Ordinary carbon is quite useless in fish keeping whereas activated carbon has wonderful uses.

Activated carbon will remove a wide variety of organic molecules by simply trapping them in the carbon pores (absorption) or by chemically bonding them (adsorption). Adsorption relies on the fact that many organic molecules are polar in nature. This means that the two ends of a molecule differ in their affinity for water. One side is repelled by water and is termed hydrophobic ("water hating") while the other end is attracted to water and is called hydrophilic ("water loving"). When a polar molecule comes close to a polar surface such as activated carbon, they become attached to each other, effectively removing the molecule from solution.*

Perhaps the most common mistake made in using activated carbon in fish keeping filtration system is its placement in trickle (OHF) filters. It is the nature of flowing water to take the path of least resistance. When activated carbon is used, it is placed so that the water must flow through the carbon, not around it. All too often, bags of activated carbon are placed in the sumps or OHF in such a manner that the majority of the water passes around the carbon and not through it.*

There are a couple of options available. One is to hook up a canister filter filled with activated carbon or part of it. Two is to use a section of PVC pipe with hose fittings at both ends. The pipe is filled with activated carbon and placed in the return line so that all of the water returning to the tank passes through it.

There are two commonly asked questions concerning the use of activated carbon: 1) how much to use and 2) how often to replace it. These questions are very difficult to quantify simply because no two systems are identical. Differences in bioloads and the kinds of fish kept types n frequency of feeding greatly influence the composition and quantity of DOC produced. The real indicators as to whether there is adequate amounts of carbon in the system are the condition of the animals being kept and the color of the water (a yellowish tint indicates a buildup of DOCs). Careful observation of the tank and its inhabitants is the key.*

As with the quantity of carbon, it is difficult to recommend a specific time period after which the carbon should be replaced. Generally, the presence of a yellowish tint in the water can be used as a guide to determining whether the carbon needs to be replaced, because the substances that tint the water are easily removed by carbon and will start to accumulate in the water when the carbon becomes saturated.*

Moe (1989) describes the following method for using water color as an indicator of carbon activity. Obtain a strip of white plastic and color one half very light yellow with a marker. Place the strip in the water and observe from a distance. When you can no longer distinguish the yellow half from the white half, the water contains significant amounts of DOC and it is time to replace the activated carbon in the filter.*

Happy reading!

[patclay]

Thanks for the info.

[AndyDwyer]

Thanks for sharing, bro