8 Tablets/pk. All that is necessary is to simply rinse, reuse, and occasionally boil your filters to remove build up, but for a deeper clean, use these eco-friendly cleaning tablets. Formulated from all-natural, organic, biodegradable and phosphate-free ingredients that eliminates oil buildup in CoffeeSock filters. Once every 6-8 weeks, boil filter(s) with 1 tablet in fresh water for 10 minutes to remove built-up coffee oils. Repeat a fresh water boil for 5 minutes. Rinse with clean water and hang to dry.