Virtually all commercial softeners use gravel under bedding. These websites use this bad claim so as to lessen their shipping cost in a desperate effort to be $1 cheaper than the next online dealer. Most online resellers of water treatment equipment have learned that if you are not the cheapest, sales will fall. Unfortunately water treatment equipment has many places where companies can save a lot of money by using lower end junk. Cheap mineral tanks, no gravel, low quality bottom screens, junk resin, etc. are just some of the ways online companies have learned to save a few bucks. Even the use of counterfeit valves and components from China has been found recently. The web site that claims gravel is not needed, while the claim from a technical standpoint may be factually correct, the rest of the claims are poorly thought out and expressed. Yes, you can build a system without a gravel bed, but no, it is not a good idea unless you are using a vortech tank design, which has its own unique issues that we wont go into here.