Check the listing for details. Eco One Six Month Maintenance Clarifier Refill Kit (ECO8037EACH). Condition: New. Listed at 124.99 USD. Eco One Six Month Refill Kit contains six bottles of SPA Monthly. A monthly maintenance organic mixture blended to clarify your spa water, soften your skin, and provide better filtration.SPA Monthly is a natural composite of minerals that draw in germs, dirt, and other pathogens to conquer and clarify the water. One of the ingredients is coconut extract that separates and branches out to gently soften skin and slowly layer the filter. This boosts filtration and allows for a less time consuming, routine cleaning. SPA Monthly will turn the water to a sparkling oasis while soothing your skin and stabilizing your pH and Alkalinity, reducing maintenance.This kit will keep a 500 gallon spa flawless and clear for six months. Start using Eco One products now to see and feel the difference of.