The 'Development of an integrated system for cost effective temperature control in aquaculture tanks' (OPTITEMPTANK) project focused on supporting the 6 000 small and medium-sized enterprises (SMEs) that work in the European aquaculture sector and the more than 50 000 SMEs in its supply chain. Land-based fish farming is the critical success factor in intensive aquaculture since it is the start of a very complicated value chain. For land-based fish farms, water is one of the most critical input factors and control of water temperature is of the utmost importance for optimal fish growth. With EU funding, the OPTITEMPTANK project delivered a system for optimal temperature control for land-based fish farms. The 12x4-metre tank is constructed from rotationally moulded segments, joined together to form a seal against the water, and with internal foaming to provide thermal insulation. A temperature control system adjusts incoming water temperatures to maintain the optimum required to promote maximum fish growth. The longer-term intention is for an innovative water heater and cooler fuelled by biogas generated from the tank's biomass waste (aquacultural faeces and food waste). Iin addition, a control system for the monitoring and surveillance of tank integrity was developed. This includes tank deformation control, system supervision and control, measuring and logging of deformation data, and remote video system surveillance. These developments come as welcome news for the tens of thousands of small companies involved in the aquaculture industry and its supply chain.