Before introducing the spore solution to your spools, you will strain the solution as one last precaution to filter out any contaminants. It is recommended that you use a sieve with a mesh size smaller than 35um. This mesh size is small enough to exclude the contaminants, but large enough for the spores to pass through. At GreenWave, we made our own sieve by cutting an 8-inch section of a 4” PVC pipe, placing the mesh over the opening, and using a 4” PVC coupling to secure the mesh. Silicone glue was then used around the edge to secure the mesh in place. To speed up this filtration step, it can help to spray down the fine mesh sieve with filtered sea water before beginning to pour the spore solution through.