4862/170=28.6. So to equal 1L of ehfisubstrat pro, you would need 28.6L of matrix just to have the same surface area. Lots of media takes more space and a bigger pump. I'd say you still over paid.Nic;1962743;1962743 said:having all 3 i wont complain about the others being good media... the price on eheim sucks... i purchased 12L of matrix for what 2L if eheim would have cost and about 4L of biomax..... i have a large sump so id rather have good Q of decent bio media than have small amount of great bio.... for the amount of media bags i have to be filled with eheim would cost me over 300$... i love the matrix it kept my tanks water perfect and even started de nitrification at its highest stock level.... its damn good bang for the buck.... i wish i could afford to use nothing but eheim substrate pro... but my wallet wont let me....