Polyp Lab High performance activated carbon in bulk - Pelleted (per pound)

Fast shipping, good communication, and the best value for replacement carbon pellets in my refillable Foodcycler cartridges. Love that it's sold by weight rather than volume.

I would like to disclaimer that I purchased with the intention of using for my 3D printer, just as Bryan and Fred. I use a more chemistry-oriented testing method by testing the pH of the carbon. I introduced them to a minimal amount of hot water. If the carbon is acid-washed with residual acid (mostly strong acid), the water should dissolve the acid with a low pH. I had the carbon soaked in hot water for 2 hours with mixing, and testing the pH at 30-minute interval. The pH values were on the neutral and alkaline side, which is definitely not acidic.

I also would like to disclaimer that I purchased with the intention of using for my 3D printer enclosure, just like Fred in the earlier review. I needed Acid Free Activated Carbon for the Bento Box filter I am building.
I did the test with some steel screws, a small bottle cap of water and some of the carbon in a air tight container. Left it in the sun and overnight for nearly 48 hours and no oxidation occurred.
I will be purchasing from here again especially given the speed of delivery too! Very happy so far to be buying from a Canadian source.

Pretty fast delivery

I want to state right off that I purchased this carbon for use in a 3D printing filter not for aquarium use. Doing so I accepted the risk that it might be unsuitable and as such tested it for my purpose, to insure it was in fact suitably acid free. I tested this using a variety of carbon steel parts cleaned of rust and oils. After 2 days of testing I am happy to report that there was no oxidation whatsoever seen on any of my test parts. I will be purchasing more of this material as I find it suitable for my purpose.
I will as a precaution test each batch received for suitability( as should anyone else) as I am indeed using it for a purpose other than for its intended purpose.
Having said all that, I am very pleased with my purchase, the speed of processing and shipping, as well as being able to buy from a Canadian source. The Carbon itself appears to be of high quality and indeed acid free.