Microbe Lift 1-Quart Pond Microbe-Lift PL 10PLQ

Does this have the same purpose as the fall/winter and spring/summer products? When would you use this product, or would you use them both together?

What is the difference between this product and Microbe-lift Sludge Away?

Do I add to the waterfall reservoir ( bags filled with lava rock) or the pond itself? Thanks

Can this be used in a pool for swimming?