Seachem Arowana Buffer

Two separate jobs, and they are worth pulling apart.

The first is buffering. Most pH products push in one direction and leave you to overshoot. This one has a destination – 6.5 – and works towards it from either side. Once there, the buffer resists the drift that otherwise happens between water changes.

The second is softening. It precipitates calcium and magnesium, which genuinely lowers general hardness (GH, your water's calcium and magnesium load) rather than masking it. For a fish evolved in soft Southeast Asian river water and living in hard Australian tap water, that half matters more.

• Targets pH 6.5 specifically – not a vague "lowers pH", a stated destination reached from above or below
• Holds for two to four weeks – Seachem's published duration, which makes this a monthly job rather than a constant one
• Softens as well as buffers – precipitates calcium and magnesium, dropping GH instead of hiding it
• Can be dosed daily in high-alkalinity water – hard tap water fights back, and Seachem's directions allow for that
• Dry powder in four sizes – no shelf-life clock the way a liquid buffer has, up to a 4 kg fishroom pack
• 1c to 2c per litre treated – the 500 g, 1 kg and 4 kg packs all work out to about 1c per litre; only the 250 g runs to 2c

• Dose once or twice a month, or as often as needed to hold pH at 6.5
• In high-alkalinity water it may be used daily until the target is reached
• It can go straight into the aquarium at any time, but dissolving it into the replacement water at a water change is the better method
• Test before dosing rather than counting doses – tap water alkalinity varies enormously across South East Queensland, and it is what decides how hard this has to work

Seachem's own dosing table pairs the teaspoon measure with a gram weight – 1 level teaspoon is 5 g at the 40 L rate. That lets pack size convert to litres treated, and to a cost per litre.

Figures assume one dose per 40 L, dosed once. Because this is a monthly maintenance product rather than a one-off treatment, a tank is dosed many times over the life of a pack – the litres figure above is a single dose's reach, which is what the cost-per-litre comparison is based on.

Suitable for: arowana tanks · soft, slightly acidic blackwater setups generally · discus, rams and wild-caught tetras kept low · tanks where hard tap water keeps dragging pH back up after every water change · anyone who wants a target rather than a direction.

Not suitable for: marine, reef or brackish aquariums · Rift Lake cichlids and other hard alkaline setups, which want the opposite · landing on a pH other than 6.5 – Seachem Acid Buffer and Seachem Alkaline Buffer together can be aimed anywhere from 6.5 to 8.0 · use as a dechlorinator, which it is not · same-day pH correction, which stresses fish more than a stable wrong figure does.

• Keep the container sealed and dry; caked powder makes teaspoon dosing unreliable
• Dissolve the dose in a jug of tank or replacement water before it goes in
• Because it softens by precipitation, expect a haze in very hard water as the calcium and magnesium drop out of solution. It clears
• Watch KH (carbonate hardness, your tank's pH buffer) as well as pH. A tank with almost no carbonate reserve left moves fast, whichever buffer you use

• Seachem pH & Alkalinity Kit – you cannot dose a buffer sensibly without reading pH and KH first
• Seachem Discus Buffer – the same idea aimed at discus rather than arowana
• Seachem Prime – dechlorinate the replacement water, because this buffer does not
• Seachem Fresh Trace – restores trace elements that softening and water changes strip out
• Seachem Matrix – biological media; arowana are large, messy fish and filter capacity is usually the real limit
• The full Seachem range – water care, media and test kits

Sold with the manufacturer's shelf life; no separate warranty term is published for a dry buffer. Your rights under the Australian Consumer Law apply regardless and cannot be excluded. A safety data sheet is published by Seachem at sds.seachem.com. Ships as a standard parcel – a dry powder, not a dangerous good. The 4 kg pack travels as heavy freight.

What pH does Seachem Arowana Buffer set?

6.5. It moves the tank there whether it is currently higher or lower, and holds it for two to four weeks.

How much do I use?

One level teaspoon for every 40 litres, once or twice a month, or as often as needed to hold 6.5. In high-alkalinity water it may be dosed daily until it gets there.

Does it soften water as well as change pH?

Yes. It precipitates calcium and magnesium out of solution, which lowers general hardness rather than simply masking it.

Is it only for arowana?

No. Anything wanting soft water around pH 6.5 suits it – discus, rams, wild-caught tetras and blackwater setups generally. The name reflects the target, not a restriction.

Can I use it in a marine tank?

No. It is a freshwater product, and pH 6.5 is far below where any marine or reef tank should sit.

How many litres does one pack treat?

At 1 teaspoon (5 g) per 40 L, a 250 g pack is good for 2,000 L per dose, a 500 g pack for 4,000 L, a 1 kg pack for 8,000 L and a 4 kg pack for 32,000 L. Because this is redosed monthly rather than used once, a pack lasts many months on a typical tank – dose by the teaspoon and confirm with a pH test.