Why our compost is the best. Oly Mountain Fish Compost® and Oly Mountain Organic Compost® are registered organic compost materials, high in organic matter and soil-building nutrients, sold through quality retail outlets in our communities. Oly Mountain Fish Compost is a virtually odorless compost and soil additive that is high in nutrients that takes over two years to become a finished product. Oly Mountain Organic Compost is an excellent compost that is weed free. It serves as an attractive soil cover in beds and effective weed mulch. The extra composting time and careful screening make them an exceptional quality product for growing healthy plants, fruits, vegetables and ornamentals. Oly Mountain products can be purchased in bulk (wholesale) at our Belfair facility, or bagged through many local retailers.