Helix 14.5" Skimmer PadThe Helix Pond Skimmer Filter Pad Used to keep fine debris from getting into your pump. A secondary defense that is placed below the skimmer basket. Especially important if you are using a magnetic drive pump. Blue is a finer, more material dense pad; this means it is better at polishing the water but would have to be cleaned more. Green is less dense, meaning it wont collect all of the fine particles in the water making it less necessary to touch as