<p><span>Fish is one ofthe example of a comestibles that contains a lot of protein and minerals, one of which is calcium. Calcium functions for the body's metabolism in the bone and tooth formation. Petek and Mujair fish contain calcium that is needed by the human body. The purpose of this study was to determine the levels of calcium contained in Petek and Mujair fish. The sampling was done by purposive sampling, which the sample used was obtained by the market in the Peunayong Banda Aceh. This research used complexometry methods. The samples of Petek and Mujair fish that had been cleared were titrated using Na2-EDTA as the titrator. The result showed that Petek and Mujair fish had different calcium levels where the calcium levels in Petek fish reach an average of 0.853% and the calcium levels in Mujair fish reach an average of 0.616%. Petek fish had higher calcium levels than Mujair fish, it was caused by their habit, where Petek fish was sea fish that contained fat, vitamins and minerals, while Mujair fish was freshwater fish that contained carbohydrates and proteins.</span></p><p><span>Keywords</span><span>: Calcium, Petek fish, Mujair fish, Kompleksometry.</span></p><p> </p>

Pot fisheries are one of the dominant activities of capture fisheries in the Penaah waters of Lingga, Riau Archipelago. This study aims to determine the effect of red LED lamp attractors on the fish catches of pots and identify the fish species. This study was conducted in the waters of Pena'ah Village, Senayang District, Lingga Regency, Riau Islands, using an experimental method. Data were collected from 18 pots for 18 days. There were three treatments, namely pot without using bait as a control, pot with red LEDs light, and pot with red LEDs light and bait, in which a total of six units of pots on each treatment. The pots caught 18 groupers during the study, of which nine individuals were captured by the pot with a red LED and bait, five individuals by the pot with a red LED pot, and four individuals without bait. The effectiveness analysis showed that the pot with red LED and bait was the highest (50%), the pot with red LED had a value of 28%, and the lowest was trapped without bait with an effectiveness value of 22%. The total catches of the pot based on the economic fish showed that adding a red LED attractor gave more types of catch than control. The red LED attractor is expected to be a solution to increase the effectiveness of the pot.