Aquasonic Algaecide

Transcribed from the Aquasonic label.

Simazine works on the photosynthetic pathway, which is why it acts across many algae types rather than one. It is also why the margin between a working dose and a dose that damages your higher plants is a matter of measurement, not luck.

Follow the Aquasonic label. Do not estimate the tank volume – measure it.

Working out your actual water volume

Aquasonic publishes the calculation on the label: length x width x water level height, all in centimetres, divided by 1000, gives litres. Use the water level height, not the tank height. Then subtract for substrate, rock and hardscape. A nominal 200 litre tank with a deep substrate and a decent aquascape frequently holds closer to 160 litres of water, and dosing it as 200 is a 25 per cent overdose.

All three bottles are the same formulation at the same 1 mL per 20 L dose rate. Only the yield differs.

A bottle this size lasts years in a single-tank household. Buy for the tank you have rather than the discount, and note that the smaller bottle is easier to shake properly – which matters more here than it sounds, because an unshaken suspension doses unevenly.

Suitable for

• Freshwater community aquariums with persistent green algae on glass, rock and ornaments
• Fish-only setups with no live plants and no invertebrates
• Tanks where light reduction and water changes alone have not cleared the problem
• Keepers willing to measure the real water volume before dosing

Not suitable for

• Shrimp tanks and any aquarium holding invertebrates. This is the firmest exclusion on the page.
• Heavily planted aquascapes. Simazine is a herbicide. Aquasonic states it will not affect aquarium plants at the correct dose, and equally states that overdosing may cause plant damage – so a planted tank has no margin for a volume estimate that is out by a fifth.
• Marine aquariums. The Aquasonic label covers freshwater aquarium use.
• Aquariums holding fish intended for human consumption. Stated on the label.
• Green water and free-floating algal blooms in a pond – this listing is the aquarium product
• Treating the cause. Algae is a symptom of light and nutrients, and this does not change either

• Do not overdose. Aquasonic states plant damage may result. Measure the water volume, then dose to that figure.
• Maintain aeration and filtration throughout. Dying algae consumes oxygen as it breaks down, and a tank that was already marginal overnight can become more so.
• Do not use in aquariums containing fish intended for human consumption. This is a label statement.
• Shake vigorously before every dose. This is a suspension. An unshaken bottle delivers an inconsistent amount of active per millilitre.
• Store closed, out of reach of children, and away from food. Keep it away from your pond and garden water sources.
• Remove dead algae as it lifts rather than leaving it to decay in the tank.

• Cut the light first. Reducing the photoperiod costs nothing and addresses the driver. Aquasonic's own instruction, if algae persists, is to decrease light exposure and increase water change frequency.
• Test nitrate and phosphate. Persistent algae in a freshwater tank almost always tracks a nutrient source – overfeeding, an overdue filter service, or tap water carrying phosphate.
• Do not stack treatments. Wait the full 14 days before repeating, and do not run a second algae product alongside this one.
• Scrape as you go. A pad or magnet removes what has already died and keeps it out of the filter.
• Watch the first 48 hours. If fish show any change in behaviour, do a substantial water change immediately.

• Seachem MultiTest Phosphate – phosphate is the nutrient most often behind a freshwater algae problem that keeps coming back.
• Red Sea Nitrate Pro Testing Kit – the other half of the nutrient picture, worth checking before and after treatment.
• Seachem Algae Scraper – for lifting the algae that dies off during the seven days rather than leaving it to decay.
• Seachem Algae Pad 3 Pack – glass-safe pads for the same job on a smaller tank.
• Aquasonic Methylene Blue – another Australian-made Aquasonic treatment, for the quarantine side of the shelf.

Aquasonic Algaecide is a consumable treatment. Your rights under the Australian Consumer Law apply to this product. Store the bottle closed and out of direct sunlight, and check the label for the batch expiry before dosing an older bottle.

Ships as a standard parcel. The 1 L bottle is a liquid over one litre, so check the current carrier restrictions if you are ordering to a remote address by air.

What is the active constituent in Aquasonic Algaecide?

Simazine, at 15 grams per litre. Simazine is a triazine herbicide that interferes with photosynthesis, which is why it works across a broad range of algae types rather than targeting one species.

How much Aquasonic Algaecide do I add?

One millilitre, which Aquasonic also expresses as 20 drops, per 20 litres of aquarium water. Shake the bottle vigorously first. Calculate the volume from length x width x water level height in centimetres divided by 1000, then subtract for substrate and hardscape.

Is Aquasonic Algaecide safe for shrimp?

No. This product should not be used in aquariums holding shrimp or other invertebrates. If you keep shrimp in the display tank, this is not the right treatment and no dose adjustment makes it one.

Will it kill my aquarium plants?

Aquasonic states the product will not affect aquarium plants provided it is used at the correct dosage, and separately warns that overdosing may cause plant damage. Since the active is a herbicide, the safety of a planted tank rests entirely on dosing to the real water volume rather than the tank's nominal size.

How long until it works, and can I dose again?

Aquasonic states results should be evident after seven days, and that the treatment may be repeated after 14 days if necessary. If algae is still present after the first course, the label's own advice is to reduce light exposure and increase the frequency of water changes alongside any repeat dose.

How much water does each bottle treat?

At 1 mL per 20 litres, the 100 mL bottle treats 2,000 litres of aquarium water, the 250 mL bottle treats 5,000 litres, and the 1 L bottle treats 20,000 litres. For a 200 litre tank that is 10, 25 and 100 full doses respectively.