Grotek� Final Flush� Removes unwanted salts from growing media Salinity can become a serious issue for those gardeners growing in containers and recirculation systems. Salt build up can cause problems for growing plants and can cause bitterness in harvested fruit. Grotek Final Flush� is a flushing agent designed to correct over feeding issues during crop production while eliminating excess salts from the medium during the final stages of plant growth. Available in original or an awesome Blueberry flavour.