## 4 Discussion  
This study aimed to evaluate the laboratory cultivation of _Chondracanthus acicularis_, focusing on key environmental parameters such as nutrient levels and light exposure. The results provide some insights into the optimal conditions for the growth and biochemical composition of _C. acicularis_, which are crucial for its sustainable exploitation in industrial applications. The study found significant differences in the relative growth rate (RGR) and productivity (Y) of _C. acicularis_ under different growth conditions. The seaweed grown on Provasoli (PES) Medium and under red LED light showed the highest RGR during the first week, while those grown on PES and with white LED light exhibited the best growth at the end of the second week. This indicates that nutrient medium and light quality significantly influence the growth rate of _C. acicularis_[60]. In the first week, the combination of PES nu  
Figure 6: Pigment content of wild and cultivated _Chondracanthus acicularis_ when grown over 14 days. VSE–Von Stoch Medium; PES–Provasoli Medium, NB–Nutribloom plus®, all grown with white LED light; blue–PES and blue LED light; red—PES and red LED light. The bars represent the mean values and standard deviations (_n_ = 3). Different letters above bars indicate significant differences (ANOVA, _p_-value < 0.05) between treatments. trient medium and red LED light likely provided optimal conditions for the initial growth phases, possibly due to the red light's influence on photosynthetic efficiency and energy absorption. Red LED light has been shown to enhance growth in specific seaweed species, as it supports higher photosynthetic pigment production [61]. In addition, the PES nutrient medium provides essential nutrients that support rapid cell division and growth. However, as the cultivation progressed into the second week, white LED light, in conjunction with the PES medium, became more favourable, likely due to its broader spectrum, which supports a wider range of photosynthetic processes and pigment synthesis [61]. The productivity results mirrored the RGR findings, with the highest Y being observed in seaweeds grown with PES and white LED light by the end of the second week. This suggests that white LED light, in combination with PES medium, provides the most favourable conditions for the growth of _C. acicularis_. These results are consistent with those of [PERSON] et al. [62], who also found that PES was the most adequate nutrient medium for the growth of Gigartinales. However, our results point to a maximum growth of 0.945% day\({}^{-1}\). These values are much lower than those found for _Chondracanthus teedei_ by [PERSON] et al. [29], who reported a maximum growth of 4.68% day\({}^{-1}\) in similar conditions. These differences may be attributed to the different species and physiological states of the algae used [23; 25]. The negative growth observed in the Von Stoch Medium (VSE), Nutribloom plus(NB), and blue LED light treatments during the first week, followed by some recovery during the second week, highlights the importance of selecting appropriate light and nutrient conditions for optimal seaweed cultivation [63]. In general, macroalgal nitrogen growth kinetics follow typical growth-saturation curves, meaning that macroalgal growth rates increase positively with increasing nitrogen concentration, and then stabilize after nitrogen concentration reaches saturation [64]. However, NB has a much higher nitrate content than the other two media, which might have stressed the red seaweed, causing growth inhibition due to nutrient imbalances and ammonium toxicity [65]. A balanced supply of macronutrients such as nitrogen, phosphorus, and potassium, together with trace elements like iron, zinc, and manganese, is essential for the growth and development of red seaweeds, as they play a critical role in the metabolic processes, pigment synthesis, and overall health of the algae [66; 67; 68]. The proximate composition analysis of _C.