The present article addresses the activities involved in the construction of two tanks for the production of Azolla (Azolla sp.), an aquatic fern that can be used as poultry feed. The activities took place in Capão do Leão and São Lourenço do Sul, in the southern part of Rio Grande do Sul state. Two models of tanks were built, the one in Capão do Leão being outside the paddocks and the one in São Lourenço do Su...