Both septic pumping and septic cleaning are important to the health of your system. While these procedures are similar, there are some key distinctions that homeowners should be aware of. To understand how pumping and cleaning are different, it’s useful to know about the main types of waste inside of your tank: Scum: The topmost layer inside of your septic tank is composed of floating waste that is actively being broken down by bacteria.  Liquid: Beneath the floating scum is the liquid layer, which makes up the majority of the volume in your tank.  Sludge: At the very bottom of your tank is sludge, which is solid waste that has been broken down and compacted beneath the liquid layer. Septic pumping is the process of removing the scum and liquid layers. Doing so will lower the volume in your tank and restore the health of the bacteria in your system. Meanwhile, septic cleaning is the process of completely emptying your tank – including the sludge at the very bottom. This will entirely reset your tank and keep it functioning like new.