Brightwell Aquatics - PHYTOGREEN-S.. Provides phytoplankton ranging in size from 1 - 2�m.. Ideally-sized for many soft corals, clams, sponges,. tunicates, tube worms, and larval invertebrates.. Formulated to provide over 1-billion phytoplankton. cells per ml.. Does not require refrigeration.. Supplemented with a proprietary amino acid to aid in. coloration of invertebrates.. Formulated by a marine scientist.Liquid. 250-ml