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This study focused on evaluating the effect of different concentrations of nutrients and total suspended solids on the removal rate of nutrients and biocompounds from the macroalgae U. lactuca in an integrated system with the shrimp Penaeus vannamei in biofloc. The experiment lasted 45 days and included five treatments with three replicates each, with percentages of 0 (control), 25, 50, 75, and 100% biofloc inoculum (73.3 ± 5.7 and 325.0 ± 21.2 mg L−1 initial nitrate and solids, respectively, in the 100% inoculum), from a shrimp farm, resulting in different concentrations of solids and nutrients. The macroalgae were introduced into 280 L tanks at a density of 0.88 kg m−2, along with 200 shrimp m−3. The algae were separated by a floating structure. Water quality parameters were measured, and the nutrient removal rate was evaluated. The treatment with 75% inoculum showed a removal rate of 55.0 ± 4.0 and 31.0 ± 10.0% of nitrate and phosphate, respectively. There was no difference in macroalgae growth between the treatments; however, macroalgae grown in 75% inoculum had higher protein, chlorophyll-a, and lower ash values compared with the control. The use of macroalgae in integrated production with shrimp under the conditions of the treatment with 75% biofloc inoculum proved to be viable and sustainable. [ABSTRACT FROM AUTHOR]

In this study, the effect of four temperatures—18, 20, 23 and 26°C—on embryonic development, growth and larval survival of the yellow clam Amarilladesma mactroides was evaluated. In the first phase, the development of the embryos to D‐larva stage was observed until all treatment groups achieved complete transformation. This process lasted approximately 28 h, with the 23 and 26°C groups showing greater transformation speed, completing the stage in 20 h 49 min. In the second phase, D‐larvae were submitted to the four pre‐established temperatures. There was a significant difference in the growth of larvae kept at 26°C when compared to 18 and 20°C. Treatments 18, 20 and 23°C produced viable pediveliger larvae; however, larvae kept at 18 and 20°C showed the fast growth accompanied by the highest survival rate. The results of this study indicate that the embryos of this species are tolerant of a temperature variation from 18 to 26°C, with the effect of this variable being a determinant in the metamorphosis. However, within the experimental conditions adopted, the larvae were dependent on lower temperatures (18 and 20°C) for settling, larger size and higher survival rate. [ABSTRACT FROM AUTHOR]