Seachem Freshwater Aquarium Alkaline Buffer, 600 g, Phosphate-Free pH & KH Support

Seachem Alkaline Buffer is a non-phosphate aquarium buffer made to raise pH and alkalinity in freshwater setups, with a target pH range of 7.2–8.5.

• Contains no phosphate — suited to aquarium conditions where phosphate buffers may contribute to algae or cloudiness concerns.
• Raises pH within the 7.2–8.5 range — gives freshwater aquarists a defined adjustment range.
• Increases alkalinity (KH) — addresses both pH and carbonate hardness.
• Designed for planted aquariums and very hard water — made for these specific freshwater conditions.
• 600 g (1.3 lbs) — a single-size buffer supply for aquarium use.

Seachem Alkaline Buffer is for aquarists who want to adjust freshwater pH and KH without adding phosphate through the buffer. Its intended settings include planted aquariums and very hard water, especially where phosphate buffers may raise concerns about algae or cloudy water. The formula is described as gentle and safe, and is intended to enhance the freshwater environment.

What water parameters does Seachem Alkaline Buffer adjust?

It raises pH and increases alkalinity, also called KH. The specified pH range is 7.2–8.5, so the product is intended for adjustments within that range rather than for every possible aquarium pH target. These two water-chemistry roles make it relevant when both pH and alkalinity are part of the aquarist’s adjustment goal.

• pH adjustment and KH increase are the stated functions.
• The stated range provides a concrete reference for the intended pH adjustment.

Why choose a non-phosphate buffer for a planted aquarium?

Seachem Alkaline Buffer contains no phosphate and is designed for planted aquarium use. This matters in settings where phosphate buffers may pose an algae or cloudiness problem; the formula lets aquarists address pH and alkalinity without phosphate in the buffer.

• Planted freshwater aquariums are a stated use case.
• Very hard water is another stated use case.

Can Seachem Alkaline Buffer be used with Acid Buffer?

Yes. Seachem Alkaline Buffer is designed to buffer with Acid Buffer, providing a named companion buffer for aquarists managing freshwater water chemistry. The product’s stated role remains raising pH and KH; its target range is 7.2–8.5.

• Acid Buffer is the specifically named buffer to pair with it.
• The package contains 600 g (1.3 lbs) of Alkaline Buffer.

Seachem Alkaline Buffer suits freshwater aquarists working with planted tanks or very hard water who want to raise pH and KH using a phosphate-free buffer. Its specified pH range and compatibility with Acid Buffer make its role clear: it is intended for freshwater pH and alkalinity adjustment, not as a general-purpose product for every aquarium need.