How do you fix hard water in a fish tank?
How do you fix hard water in a fish tank?
How to Decrease Water Hardness in the Aquarium
Use a RO/DI System. A reverse osmosis deionization system filters out all the particles in the water that goes through it, even stripping away the minerals.
Add Aquarium Soil.
Add Driftwood.
Add Other Sources of Tannins.