I need help with this please. Also is there a better way to get the hardness out of my water?
It goes in the filter so it comes in contact with the maximum amount of water. Another, slightly safer way (though if you’re going to chemically soften the water, the resins in pillows are best, in my opinion), is to put small amounts of peat moss (either from the pet store, or organic/untreated sphagnum moss from garden stores) in the filter. Also, adding a fair bit of driftwood will have the same affect as peat on a smaller scale. As a last resort, you could mix your tap water with reverse osmosis water, which is almost entirely pure, and will lower the concentration of the dissolved minerals that constitute water hardness.