Bird net selection requires the identification of the particular species causing the problem. Bird size in relation to mesh size is not only important for the purpose of exclusion but also as much as it is for inclusion. Its important to consider those insect species that are beneficial for which you don't want to exclude eg those that are responsible for the process of pollination.
If you're seriously looking for a return on your investment bird netting is a necessity.
We have various netting coverage options available big or small - temporary or permanent for the small suburban fish pond to the large commercial investment.