- Sku: 234
- Vendor: Seachem
Seachem Alkaline Buffer
Seachem Alkaline Buffer is a non-phosphate buffer that raises pH and carbonate alkalinity (KH) in freshwater aquariums. It is the go-to choice for soft, acidic source water and for fish that prefer harder, higher-pH conditions, such as African Rift Lake cichlids, livebearers, and goldfish. Browse more Seachem water care in our additives and supplements section.
Why Alkaline Buffer
- Raises pH and KH together toward a stable 7.2 to 8.4 range.
- Non-phosphate formula that builds carbonate hardness without adding phosphate that can feed nuisance algae.
- Pairs with Seachem Acid Buffer to dial in and hold almost any pH between about 6.5 and 8.5.
- Gentle and adjustable, so you can move water chemistry in small, controlled steps.
- Concentrated dry powder that stores indefinitely and goes a long way.
Choose Your Size
| Size | Approx. 1/4 tsp doses* | Best for |
|---|---|---|
| 70 g (2.5 oz) | about 45 | Nano and single small tanks, or trying it out |
| 300 g (10.6 oz) | about 200 | Mid-size tanks or regular weekly dosing |
| 600 g (1.3 lb) | about 400 | Large tanks, fish rooms, best value per gram |
*Each 1/4 teaspoon (about 1.5 g) treats roughly 80 L (20 US gallons) and raises carbonate alkalinity by about 1 meq/L (2.8 dKH).
How to Use
Use 1/4 teaspoon (1.5 g) for every 80 L (20 US gallons) twice a week, or as needed to reach your target pH. For best results, dissolve the dose in a cup of tank water first, then add it to the aquarium. Raise pH gradually, no more than about 0.2 pH units per day, so fish can adjust comfortably.
Setting an Exact pH with Acid Buffer
Used on its own, Alkaline Buffer pushes pH toward 8.0. To target a specific lower value, combine it with Seachem Acid Buffer in these approximate ratios:
| Target pH | Acid Buffer : Alkaline Buffer |
|---|---|
| 6.6 | 1 : 1 |
| 7.0 | 1 : 2 |
| 7.4 | 1 : 4 |
| 8.0 | Alkaline Buffer only |
Always test your pH and KH before and after dosing, and adjust the ratio to suit your tank.
Specifications
| Product | Seachem Alkaline Buffer |
| Type | Non-phosphate pH and alkalinity (KH) buffer |
| Water type | Freshwater |
| Adjusts | Raises pH and carbonate alkalinity (KH) |
| Target pH | Up to about 8.0 alone, lower values with Acid Buffer |
| Dose | 1/4 tsp (1.5 g) per 80 L (20 gal), 2x weekly or as needed |
| Alkalinity per dose | About 1 meq/L (2.8 dKH) |
| Form | Dry powder |
| Sizes | 70 g, 300 g, 600 g |
| Made in | USA |
Good to Pair With
- pH and KH test kits to track your water before and after each dose.
- Seachem Alkaline Regulator, a phosphate buffer that locks freshwater pH near 8.3 for African cichlid setups.
- More Seachem conditioners and buffers for fine-tuning water chemistry.
FAQ
What does Seachem Alkaline Buffer do?
It raises pH and carbonate alkalinity (KH) in freshwater. Higher KH also helps hold pH steady so it does not drift down between water changes.
Will it cause algae like some pH buffers?
No. It is a non-phosphate formula, so it buffers without adding the phosphate that can fuel nuisance algae.
How is it different from Seachem Alkaline Regulator?
Alkaline Regulator is a phosphate buffer that locks pH near 8.3, which suits African cichlids and other high-pH tanks. Alkaline Buffer is non-phosphate and fully adjustable, especially when paired with Acid Buffer.
Is it safe for plants and invertebrates?
Yes, when used as directed. Raise pH and KH slowly and test first, since some soft-water shrimp and plants prefer lower, softer conditions.
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Seachem Alkaline Buffer
