A pilot version of a web interface primary data shell has been developed. The shell was pre-tested by a selected group of dedicated partners, improved and launched for testing by partners in the whole AQUACOSM-plus community. By a couple of introductory meetings, partners were shown the procedure to enter a mesocosm experiment and add primary data. Partners had the opportunity to test the platform for 2,5 months and give feed-back with suggestions of improvements. Suggestions for improvements were noted from the partners and additional improvements were furthermore identified by the task group itself. No major requirements of changes of the basic structure of the primary data shell were requested. Most suggested improvements for the six prioritized variables are planned to be remedied within the project period. The need of resources to develop a fully operational shell will be presented in the final report from this task.