Seaweed systems for Integrated Aquaculture (IMTA)

Seaweed is a wonderful crop to purify the water around fish farms in open sea and producing valuable protein and other interesting compounds in the same time. Fish farmers will benefit from this system by the immediate uptake of excretes from the fish like ammonia and secondary formed nitrates and phosphates. The eutrophication of the surrounding waters is prevented helping the ecosystem to be stable. The seaweed fields give protection against natural enemies of sealice, like the appreciated lipfish. If every fish farm grows 20 ha of seaweed in the proximity of its cages the environmental effect is significant. It would help to produce about 15% of the needed feed proteins for raising the fish in the same time, saving the same amount of fishmeal. Seaweed proteins are in amino acid composition and digestibility comparable to fish proteins. Hortimare BV provides the seaweed farmers with juvenile seaweeds and the supporting cultivation systems to grow them. These consists of seaworthy floaters and horizontal growing lines.