Review on 🥤 Matrix, 2 Liters / 67.6 Fluid Ounces by Amy Hodgson

As others have said, many of the stones contained in this product are not the porous material advertised. About 1/3 of all the rocks in the container are a mix of granite and obsia or lower quality porous material, which is absolutely ridiculous. I'm usually a fan of Seachem. They make great products like Purigen and Prime but this product is rubbish. Seachem can easily separate waste rock from porous rock because porous rock is lighter. Some of these stones will even float when first dipped in water! This is a terrible quality control problem that can easily be solved with a specific gravity or density grading machine. Instead, they sell you a bag full of dirty rocks that you have to hand wash and sort in a couple of hours. Say, when you go to the hardware store and buy a bag of rocks for your garden, do you spend the rest of the day sorting and cleaning those rocks? Of course not! That's just laziness on the part of Seachem. In addition, Seachem claims that this material removes nitrates, but the bacteria needed to remove nitrates do not form when used in canister filters. In fact, all other companies that sell biological filter media don't advertise that their products remove nitrates because while it's technically possible, it will never happen on a measurable scale, again showing how Seachem positions this snake oil as the end. - all filter materials! Save some money and hours of your life by sifting through the junk and just buy the good old Eheim Substrata Pro. One more thing - if you buy this junk, Seachem says you don't have to use filter bags for this material, but the material varies in size from sand to pea-sized to small pebbles. A bag filter is a necessity for this material. Sand-sized items naturally end up in the trash, but a bag is essential to hold any goodies you find panning and sifting rocks.