Check the listing for details. DEEP BLUE CARBON LABORATORY GRADE ACTIVATED 39 OZ ADB41012. Condition: New. Listed at 19.99 USD. Carbon Listing is for ( 1 ) : DEEP BLUE Premium Carbon Activated Carbon In Jar With Media Bag - 39 oz Activated carbon filter media aggressively adsorbs organic pollutants from medicines and metabolic wastes, detoxifies harmful gases and removes unwanted colors or odors from your water. Coal based activated carbon is more porous and affects your pH less than coconut based carbon. We recommend medicating sick fishes in a separate quarantine tank, but if you have to use your main tank, remove carbon first and replace afterwards to remove remaining medicines. Carbon removes trace elements needed for plant and invertebrate growth, so make limited use of it in planted and reef aquariums, and always monitor your water conditions. Thank you ! Please feel free to contact me for International and combined auction shipping rates or with any questions or concerns that you may have about my products. Thank you !