Experimental indoor cultivation of the carrageenophytic red alga Gigartina skottsbergii

Exploitation of carrageenophytic seaweeds in Chile has increased significantly over the past few years. Gigartina skottsbergii is one of the species exploited and the harvesting pressure could have negative consequences on the sustainability of this resource. Although demand for raw material of G. skottsbergii continues to increase, basic knowledge needed to cultivate this unique carrageenophyte is lacking. In this study, we determined the light, temperature, and nutrient requirements for juvenile G. skottsbergii cultivation, as well as the culture system and stocking densities required to optimize its indoor cultivation. An optimal temperature range of 10-14degreesC combined with dim light conditions are recommended. Nutrients do not need to be constantly added and ammonium instead of nitrate should be used, whereas phosphate must be also added. Floating cultures provide an adequate alternative, where containers support loads of 13-14 g (fresh weight) L-1. Only in very precise combination of factors, the specific growth rate can be over 2% per day. (C) 2004 Published by Elsevier B.V.