[nabla9]

Even if it's not a bogus, they are rarely practical. Just like when adult hobbyists invent these things and they work, the engineering constraints of cost and scalability or negative side effects usually kill the project.

In this example, how much vegetable oils and magnetite powder you need per cubic meter of water?

[Ekaros]

Also how big magnets are we talking about here? And what scale of flow they can operate at with sufficient efficiency? Also what if there is lot of surfactants(soap etc.) involved in water?