KH booster (carbonate buffer)
Product to increase the carbonate hardness (KH) of water. Stabilises the pH, preventing dangerous fluctuations.
Detailed explanation
KH (carbonate hardness) is the buffer system of water. Adequate KH prevents sudden drops in pH that can kill fish.
Common products: sodium bicarbonate (NaHCO3, the cheapest), Seachem Alkaline Buffer, Salty Shrimp GH/KH+.
The dosage of sodium bicarbonate is simple: 1 teaspoon (about 6 grams) per 100 litres raises the KH by about 1 dKH.
The target KH In freshwater aquariums is 3-8 dKH for most fish. For Caridina 0-1 dKH (the active substrate buffers the pH independently of KH).
Too low a KH (below 2 dKH) makes the pH unstable: at night the CO2 from breathing can cause the pH to drop to dangerous levels.
Reference values by aquarium type
| Aquarium type | Recommended range |
|---|---|
| Tropical freshwater | 3 - 8 dKHFor most tropical fish |
How it is measured
KH drop test (API, JBL, Salifert).
What happens when it is too low
Unstable pH. Risk of pH collapse during the night.
What happens when it is too high
Difficult to lower the pH. Not ideal for soft water fish.
Coralia Lab monitors this parameter with AI diagnostics. Tank Score alerts you when a value moves outside the recommended range for your aquarium.
Try AI diagnostics for free