TECHNOLOGY FOCUS - BIOLOGY - Preferred Component: The grazers comprise rotifers, Moina, daphnids or their combinations. Preferred Microorganism: The algae are green algae, red algae, brown algae, golden-brown algae, blue-green algae (Cyanobacteria), diatoms, or their combinations, preferably Amphipleura, Chlorella, Botryococcus, Dunaliella, Gracilaria, Nannochloris, Nannochloropsis, Pleurochrysis carterae, Sargassum, Scenedesmus, Spirulina, Ulva or their combinations. The algae are macroalgae, preferably seaweed. The algae grown in the presence of grazer, grow to 80-100% of control algae-absent grazers.    TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Components: The biocide is synthetic hormone or its analog, preferably methoprene. The medium comprises methoprene (1-100 mg/l), and terpene (500-625 ppm). The biocide comprises terpene. The terpene is alpha -pinene. The biocide comprises a limonoid chosen from limonin, nomilin, nomilinic acid, azadirachtin, cedrelanolide, toosendanin, ichangin, obacunone, 12-hydroxyamdorastatin, isofraxinellone, melatonin, and their derivatives. Preferred Method: The method involves genetically modifying the algae to produce the terpene.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The adjuvant is chosen from acetone, propylene glycol and nonylphenyl ethoxylate. The adjuvant comprises anionic surfactant, cationic surfactant, nonionic surfactant, amphoteric surfactant or their combinations. The anionic surfactant is chosen from fatty acid sulfates, fatty acid ether sulfonates, alkyl aryl sulfonates including sulfonate of dodecyl benzene, fatty acid salts, mono, di, tri-aryl poly-glycolether phosphoric acid esters and their salts. The cationic surfactant is chosen from quatenary ammonium salt and its phenyl derivative. The nonionic surfactant is chosen from polyethoxylated castor oil, sorbitan, sorbitan esters, fatty alcohols, acids and esters, alkylphenols including nonylphenol ethoxylate, block polymers of ethylene and propylene oxide and their alkyl, aryl or alkylaryl condensates. The amphoteric surfactant is alkyl betaine. EXAMPLE - No suitable example given.