I have been read a lot about black diamond blasting media trying to figure out if I want to use it or not for my new tank. This will be talking about the blasting media from TSC specifically. I have come across a lot of people for or against it, and don't know if I can trust their opinions on it knowing nothing about their aquarium background. So, I underwent researching it to get as much info as possible. In my 20 gallon I use #20 grade pool filter sand, which is a pretty small grain size. The blasting media in question measures a 20-40 for the mesh size which equates to 0.031"-0.0165", so it is the grains are the same size and smaller than the PFS. The PFS should technically be a fairly uniform size at 0.031". So, the size is comparable. The main thing that raised a red flag for me was the blasting media is coal slag, and I knew little about it. Having used many other blasting media I know it can have some pretty rough grains, and I found that out when I didn't notice my arm was exposed. Anyway, I found an article explaining that it is an inert product making it environmentally safe. Also, seeing the MSDS for the product shows that it is made up of a majority of coal slag with a small amount being crystalline silica. It looks as though dust is to be expected, so rinsing it heavily would be needed. Seeing all of this makes and members here using it makes me think it is safe to use. The edges of it seem to be described as "sharp" and "angular" by various places. Then again sand isn't very smooth to me either. Now for the questions I have. Has anyone compared this to other sand they have? I have a theory that, while wearing gloves, I can move the media around against the other pieces dry, and essentially wear down the edges some. It seems possible, but it may be a waste of time. I am open to hearing more either for or against using this. Otherwise I may just give it a try and compare the two. I know this may be overkill on research, but it may help put my mind at ease.