Aquaculture is one of the fastest growing agricultural activity in the last decades due to its great potential for expansion, which has not been explored yet.However, it is interesting that this growth should be directed toward a conscious production that aims the sustainability of production, taking advantage of ecosystem goods and services that may favor the attainment of this objective.Marine Integrated Multi-Trophic Aquaculture (IMTA) is an alternative to achieve this goal.The production is based on the recycling and reuse of resources, which makes IMTA aligns higher aquaculture productivity with a lower ecological footprint.The aim of this work was to understand the interactions between the open water integrated cultivation of the red macroalgae Gracilariopsis tenuifrons and the mussel Perna perna in the cove of Mar Virado, in the Ubatuba city.In the Chapter 1, we tested techniques for growing macroalgae strains under semi-controlled conditions that aims to maintain healthy seeding with a low maintenance cost.They were tested for algal densities of culture (gram of algae per liter of culture medium) and we used a cheapest source of nutrients, the commercial Forth® 30-10-10 orchid fertilizer.Gracilariopsis tenuifrons showed preference for 1 g.L -1 density cultivation and showed good results for the use of orchid fertilizer.The algae also showed good results for growth rates, with rates higher than 6 %.day -1 .In Chapter 2, an open water integrated cultivation was carried out between the macroalgae G. tenuifrons and the mussel P. perna, with the aim to character the environment of a marine farm in relation to its interactions between the integrated cultivation of mussels and the macroalgae and the environmental factors.The macroalgae were cultivated at different points of the marine mussel farm, in these places we measured biotic and abiotic parameters such as nutrient concentration, velocity and direction of water flow, solar irradiance temperature and growth rates of macroalgae.The chemical algal composition at each culture point was also analyzed.The results showed that there is a difference in the growth of macroalgae at different points, where the nutrient flow from the mussels was higher, with higher growth rates and a higher concentration of compounds in the algal material such as proteins, pigments and carbohydrates.Thus, the knowledge of the dynamics of the integrated crop area is good for a better production.