Your journey to a better aquarium begins today CONCENTRATED Guillard's F/2 Phytoplankton Fertilizer 16oz This is a commonly used enrichment solution used in the culture of marine phytoplankton. Directions: Simply add 1 ml to 1 L (2 ml to a 2 L pop bottle) of fresh saltwater at ~1.019 s.g., add your starter culture and light ~16 hours per day. A 16 oz bottle is enough for approximately 480 liters at f/2 concentration! Keep in a cool, dark area and shake prior to use. Check out our other items for starter cultures of Nannochloropsis on agar plates or as liquid cultures! Shipping Information All orders are shipped within 24 hours M-F. If you order later in the day on Friday or on Saturday or Sunday, your order will ship early Monday morning. Return Information If you are not 100% satisfied with your purchase, you can return the product and get a full refund or exchange the product for another one. You can return a product for up to 14 days from the date you purchased it. Any product you return must be in the same condition you received it and in the original packaging. On Mar-12-18 at 15:11:34 PDT, seller added the following information: