activated carbon controversy

[ml708]

http://www.drtimsaquatics.com/resources/library-presentations/aquarium-hobby/activated-carbon

"There is much written about the use of carbon in seawater aquaria. Some authors recommend against the use of carbon in seawater aquaria because carbon will remove trace elements. As with most situations in the aquarium hobby, the correct response to the claim that activated carbon removes trace elements from seawater is yes and no– mostly no. By definition, trace elements are those elements found in the ocean with a concentration of less than 1 ppb. These are elements such as cesium, chromium, cadmium, selenium, cobalt, silver, lead, tin, helium, lanthanum and cerium. For these elements, it has never been shown that they are really needed in the aquarium. In fact, adding some to the water would really be poisoning the tank. Further, these elements are rather insoluble at the pH of seawater, so activated carbon cannot remove them from the water. Thus the correct technical answer is that in the normal marine aquarium, activated carbon will not remove trace elements. However, if one wanted to remove some of the above listed trace elements from seawater with activated carbon it could be done by changing the pH and some other factors to get the elements in the soluble form but this would render the seawater uninhabitable.

So what elements might carbon removes from seawater that would be of interest to the marine hobbyist? These elements would be copper, iodine, iron and molybdenum which, by definition, are called minor elements. However, once again, how much of any of these elements carbon might remove depends upon the element’s solubility in seawater. Most of these elements are not in the soluble form in seawater and, as such, cannot be removed from the seawater by carbon. The bottom line is that activated carbon is going to have no effect on the majority of elements found in seawater.

Activated carbon should be part of every aquarium filtration system. This is another statement that some have disagreed with me about. However, personal experience with using activated carbon for years along with data collected in my laboratories supports my claim. Carbon has been used continuously in all types of freshwater tanks, saltwater fish-only tanks, reef tanks and large display systems in the labs and never has there been a problem.

The reasons given for not using carbon or not using it continuously include: the carbon causes some diseases, it removes beneficial elements/substances for the water, and eventually the carbon will de-adsorb everything killing the tank inhabitants. None of these reasons have ever been supported by experiments or tests. Rather, they are myths. And as myths, they circulate through the hobby growing a life of their own which becomes hard to kill."

According to experiences of the bros here, do you agree with him that activated carbon is actually good chemical filtration for a reef tank?

[LittleBurger]

I know to raise the orp, I had dump in 1500g of carbon into my filter sock. Overnite my orp went from 290 to 400+. But what came next was sps start to bleach. So besides sudden raise of kh would endanger the sps, orp will too. Overall I think carbon is used as a media to neutralize "poison", I think for tanks with only hard corals dun need them. But tanks with hard n soft corals would need them. This is my personal observation of my tank.

[Martian]

I know to raise the orp, I had dump in 1500g of carbon into my filter sock. Overnite my orp went from 290 to 400+. But what came next was sps start to bleach. So besides sudden raise of kh would endanger the sps, orp will too. Overall I think carbon is used as a media to neutralize "poison", I think for tanks with only hard corals dun need them. But tanks with hard n soft corals would need them. This is my personal observation of my tank.

Bro... Sorry for my ignorance but what is "orp"?

[LittleBurger]

Bro... Sorry for my ignorance but what is "orp"?

Gd read and better explanation by expert. http://reefkeeping.com/issues/2003-12/rhf/feature/