Look at body color. Good fish fry have the same group of pigments, and their body color is fresh; poor fish fry have different Pigment groups and their body color is slightly white. Second look at the composition of groups. Good fry were tidy, plump, smooth and not muddy, swimming and lively; poor fry were smaller, ranging in size, and dragging mud. Three to see the ability to move. Put the hand or wooden stick into the middle of the seedling bowl and the seedling dish to make the fry startle. The good fry move around quickly; the poor fry is unresponsive. Fourth, look at the counter-current flow. Stir the fish body with your hands or a wooden stick to swirl the water. The good fry can swim against the water along the edge; the poor fry is caught in the whirlpool and is unable to struggle. If the fish fry in the white porcelain basin, let the wind blow the water, so that the fry can swim against the wind; poor fry can not. Five look at the ability to struggle. Put the fry into the white porcelain dish and drain the water. The fry will be struggling and the head and tail will be bent into a round shape. The poor fry will not be able to struggle and only tremble. Food additives are compounds or natural substances added to food for the purpose of improving the color, aroma, and taste of food, as well as for the needs of anti-corrosion and processing technology. At present, there are 23 categories of food additives, with more than 2,000 varieties, including acidity regulators, anticaking agents, defoamers, antioxidants, bleaching agents, leavening agents, coloring agents, color retention agents, enzyme preparations, and flavor enhancers, nutritional fortifiers, preservatives, Sweeteners, thickeners, spices, etc. Erythritol, Sweetener, Pigment, XOS , Carotene, fish oil Xi'an Gawen Biotechnology Co., Ltd , https://www.ahualynbios.com