Water Conditioners & pH

API Aquarium Salt

FreshwaterAll-natural

API Aquarium Salt is a freshwater tonic made from evaporated sea water. It supplies the electrolytes fish use to take up oxygen and release carbon dioxide and ammonia through their gills — electrolytes that tap water and soft water often lack. A rounded tablespoon per 20 litres, or half a rounded teaspoon per 4 litres, supports gill function and reduces stress when setting up a new tank, at water changes and during disease recovery. It is also the salt used to recharge API Nitra-Zorb and the Water Softener Pillow. The carton holds 454 g. Take care with live plants, as some are salt-sensitive.

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Live pricing and stock on jungleaquatics.com — purchase through Jungle Aquatics, with delivery across South Africa.

Dosage calculator

Enter your aquarium volume and the calculator works out how much API Aquarium Salt to use for each rate on the pack.

Aquarium volume

Measured in

Use the water the tank actually holds, less substrate and decor.

Standard tonic dose1 tablespoons per 20 litres
Enter a volumeAt set-up, with water changes and during disease recovery

Dose only the water you actually replace — salt is not lost to evaporation, so topping up does not need more.

A guide only — always follow the dosing instructions printed on the pack, and measure with the bottle's cap or a syringe rather than by eye.

Technical details

Product type	Evaporated sea salt tonic for freshwater aquariums
Pack size	454 g carton
Dose	1 rounded tablespoon per 20 litres, or ½ rounded teaspoon per 4 litres
When to use	New tank set-up, water changes, disease recovery
Suitable for	Freshwater aquariums
Safe with	Freshwater fish; use with care around salt-sensitive plants
Also used for	Recharging API Nitra-Zorb and the Water Softener Pillow
Made by	Mars Fishcare, USA

Salt does not evaporate — add it only for the water you replace at a water change, never for topped-up evaporation.

How much salt do I add, and when?

Add one rounded tablespoon for every 20 litres — or half a rounded teaspoon for every 4 litres in a small tank — dissolved in a jug of tank water before it goes in. Use it when you set up a new freshwater aquarium, for the new water at a water change, or when fish are recovering from disease. Because salt stays in the tank when water evaporates, dose only the water you actually remove and replace, or the level creeps up. The 454 g carton is about 25 tablespoons, enough to treat roughly 500 litres of new water. Go carefully in planted tanks: some species tolerate salt poorly.

Electrolytes for gill function

Freshwater fish constantly lose salts to the water around them, and in very soft or heavily changed water they struggle to keep up. A low level of aquarium salt restores the electrolytes that drive oxygen uptake and waste release across the gills, which is why fish under stress or recovering from illness often perk up after it is added.

Three moments to use it

Add it when setting up a new freshwater tank, with water changes, and when treating disease — API is specific that it is for those situations rather than constant heavy dosing. The measure is one rounded tablespoon for every 20 litres or half a rounded teaspoon for every 4 litres, dissolved in a little tank water first.

Made from the sea, used in fresh water

It is pure evaporated sea salt, not table salt: no iodine and no anti-caking agents. That also makes it the right salt to dissolve for recharging ion-exchange media such as Nitra-Zorb and the Water Softener Pillow. It is not a marine salt mix and will not make saltwater for a marine tank.

Frequently asked questions

Can I use table salt instead?

Not advisably. Table salt carries iodine and anti-caking agents; API Aquarium Salt is plain evaporated sea salt with nothing added, which is what fish and ion-exchange media need.

Is aquarium salt safe with live plants?

Many common plants tolerate the label dose, but some are salt-sensitive, so API advises extra care in planted tanks. Start with a reduced dose and watch for leaf damage.

Can I make saltwater for a marine tank with it?

No. It supplies electrolytes to freshwater fish; a marine aquarium needs a complete synthetic sea-salt mix with the full range of major and trace elements.

Do I add salt every water change?

Only for the volume you replace. Salt is not lost to evaporation, so treat the new water at the dose on the pack and never the whole tank again unless you have done a complete change.

Is API Aquarium Salt available in South Africa?

Yes — Jungle Aquatics in Fourways, Johannesburg stocks the 454 g carton and delivers across the country; live pricing and stock are on jungleaquatics.com.

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