Additives series， used for keeping aquarium environment， are contained in an eye drop container， which is easy to supply a small amount in the aquarium. Like liquid fertilizer series， economical large volume bottles are also available for refill. * Please follow the suggested dosage amount on the instruction manual for the first time use. Then adjust the supply amount depending on the aquarium condition after getting the knack of it. GREEN GAIN Green Gain is an additive helping the plant spread new leaves after trimming. It contains trace elements extracted from sea weed and plant hormone. It reduces plants’stress and enhances their growth.