Do I really need to double strain the finish?
When coating with waterbased sealers or finishes, it is always a good idea to strain the product on every coat. During transport the finish can develop a film on the top of the bottle above the fill line. Once the film dries it may fall back into the finish leaving small flakes or clumps that may not be apparent until you pour out the product.
Avoiding leaving solids on your floors with a simple technique.
Many manufactures provide a filter with the product that will help catch most of the solid particular before they reach the floor. As best practice, double straining with paint strainers or nylon pantyhose will help reduce the likelihood that no solids end up on the floor.
Place the coarse filter inside of the pantyhose, stretching the hose out until the fabric is taunt. Place the coarse filter in the mouth of sealer or finish. Remove the excess pantyhose.