How to Make Water Softer in a Fish Tank

Tanks that maintain consistent levels of water hardness have fewer problems.

Poor water conditions make fish more susceptible to disease and illness. Hard water conditions are created by increased amounts of calcium and magnesium, which directly affect the pH level throughout the tank. However, before the pH level can be maintained, the water must be softened using a quick temporary means in conjunction with installing special filters for a long-term solution. Taking a layered approach to maintaining optimal water conditions results in healthier, stronger fish.

Things You'll Need

• Water pH conditioners
• Water pillow
• Non-soluble aquarium rock
• Peat moss
• Reverse osmosis filtering system
• Water test strips for pH, calcium and magnesium

Instructions

1. Perform a water quality analysis on your water source and tank water. This provides you with baseline water quality readings before you begin changing your tank conditions.

2. Pour a water softener or pH stabilizer into the tank, according to the directions on the box. This immediately starts to reduce water hardness and achieve desired pH levels.

3. Place a piece of clean, natural peat moss or commercially manufactured water pillow in the tank, to enhance water softening properties. The pillow catches the calcium and magnesium, and contributes to maintaining correct pH levels.

4. Replace coral rocks and other calcium-carbonate-based gravels with less soluble ones, such as slate and granite.

5. Incorporate a reverse osmosis filtering system, to achieve consistent desired levels of water softness. Reverse osmosis filters also reduce temporary water hardening spikes in calcium and magnesium, due to partial water changes.

6. Check water quality weekly to maintain proper pH, calcium and magnesium levels.

7. Replace pillows, moss and filters as directed by the manufacturer, to maintain optimal water conditions.

8. Add pH stabilizers when needed, to address spikes in water hardness.

Tips & Warnings

• Find out the specific level of pH your fish require, to determine how soft to make your water.

• Perform partial water changes with clean-sourced, collected rainwater in nonmetallic containers, to assist in maintaining a softer water quality.

• Make changes gradually, such as over a period of a week, to allow time for the products to take effect and the fish to become adjusted to them.

• Quick and extreme changes in water conditions can compromise the health of your fish, and result in illness or death.

• Do not collect or use rainwater from highly polluted areas, or from concrete or metallic runoff systems.

References

• Doctors Foster and Smith: Common Water Quality Issues & Remedies
• Sidney Cichlid Aquarium Pages: Water Hardness Frequently Asked Questions
• Doctors Foster and Smith: Water Softner Pillow