D.E. – Diatomaceous earth is a powder filtering agent made up of tiny sea diatoms. It attaches itself to the grids of a D.E. filter and filters out very small particles.
D. E. Filter – Diatomaceous Earth Filter – A filter designed to use diatomaceous earth (D.E.) as the filter medium. The D.E. is added through the skimmer with the pump on, which takes the D.E. and deposits it on a grid. The D.E. then becomes the filter medium.
Decking – In the swimming pool industry, decking is generally assumed to be concrete unless the term is proceeded with a different type. For example, brick decking or wood decking.
Decks – Those areas immediately adjacent to a pool, spa or hot tub that are specifically constructed or installed for use by bathers for sitting, standing or walking.
Defoamer – Also called anti-foam – A chemical added to the water to make the suds or foam go away. These products do not remove the source of the sudsing. Most often, the water must be drained and refilled to remove the soaps, oils and other causes of foaming. Shocking and super chlorination may help prevent foaming.
Diatomaceous Earth – Also called D.E. – A white powder composed of fossilized skeletons of one-celled organisms called diatoms. The skeletons are porous and have microscopic spaces. The powder is added through the skimmer with the pump on and deposits itself on a grid. The powder then becomes the filter medium.
Dichlor – The common name for sodium dichlor. A fast-dissolving chlorine compound containing chlorine and cyanuric acid (stabilizer or conditioner). It has a neutral pH and is quick-dissolving, so it can be used for regular chlorination or super chlorination.