Cobalt sol'n; 1,000 ppm. Increases cobalt in recirculating seawater systems. Increases primary productivity. Required by photoautotrophs (including zooxanthellae) for photosynthesis, and pigment, vitamin, and enzyme production. 1 drop (0.05 mL) per 7,472 gal. (28,281 L), once daily to maintain NSW value for S=35. 1,000 ppm cobalt, derived from cobalt chloride (hydrated source, USP).