sera marin GVG-Mix Nature is the natural staple food for marine fish that does not require dyes and preservatives. The mixture of flakes and dried whole food organisms such as Krill bloodworms and daphnia allows for a varied diet. The food is rich in natural minerals and trace elements such as iodine and thus supports health and fertility. The flakes keep their shape are suitable for all surface oriented marine fish and do not cloud the water.