Pond Care

API Pond Ammo-Lock

PondDetoxifies ammonia

API Pond Ammo-Lock converts the ammonia a stocked pond produces continuously into a form that is safe for fish, while leaving it available as food for the bacteria in the biological filter — so the pond keeps cycling rather than simply masking the problem. It also removes chlorine and chloramines, which makes it useful for the water change that should accompany any ammonia reading. Dose 60 ml for every 900 litres, or 240 ml for every 3 600 litres. It comes in 473 ml and 1.89 litre bottles, and its effect can be tracked with API ammonia test kits.

Size: 473 ml

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

Dosage calculator

Enter your pond volume and the calculator works out how much API Pond Ammo-Lock to use for each rate on the pack.

Pond volume

Measured in

Use length × width × average depth in metres × 1 000 = litres.

Ammonia treatment60 ml per 908 litres
Enter a volumeAfter a partial water change; repeat while ammonia is detected

Stop feeding for a few days and check the filter — ammonia is a symptom, not the cause.

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	Liquid pond ammonia detoxifier and dechlorinator
Sizes	473 ml · 1.89 L
Dose	60 ml per 900 litres, or 240 ml per 3 600 litres
Removes	Ammonia (detoxified), chlorine, chloramines
Suitable for	Garden and koi ponds
Testing	Detectable with API ammonia test kits
Made by	Mars Fishcare, USA

Ammonia in a pond usually points to overfeeding, overstocking or a filter that is not keeping up — treat the cause as well.

My pond tests positive for ammonia — what now?

Do a partial water change first, treating the new water for chlorine, then dose Ammo-Lock at 60 ml per 900 litres of pond water — a 5 000-litre pond takes about 330 ml. Stop feeding for a few days: uneaten food is the most common cause. Check that the filter is running and has not been over-cleaned, and rake out decaying leaves and blanketweed. Retest with the Pond Master Test Kit after 24 hours and repeat the dose while ammonia is still detected. In spring, when fish begin feeding before the filter bacteria are fully active, a little ammonia is common — feed sparingly until the readings settle.

Ammonia made harmless, not hidden

Fish waste, uneaten food and decaying leaves all release ammonia, and in a pond warmed by the South African sun the toxicity of that ammonia rises with temperature and pH. Ammo-Lock binds it into a non-toxic form that fish can tolerate and that the pond’s bacteria continue to process in the normal way.

Feeds the biological filter

Because the bound ammonia remains available to nitrifying bacteria, the product supports the pond’s natural filtration rather than starving it. That matters in spring, when fish start feeding before the filter bacteria have fully woken up.

Dechlorinates the water you add

Ammo-Lock removes chlorine and chloramines, so it treats the replacement water during the partial change that any ammonia problem calls for. Test, change water, dose, and test again.

Frequently asked questions

Will my ammonia test still read positive after dosing?

API states that Pond Ammo-Lock is detectable by its ammonia test kits, so you can track the change with the Pond Master Test Kit and see the reading fall as the filter clears the bound ammonia.

Does it stop my biological filter working?

No. The bound ammonia remains available to the nitrifying bacteria, so the filter keeps processing it while the fish are protected.

Can I use it when adding new water?

Yes. It removes chlorine and chloramines as well as detoxifying ammonia, which makes it a sensible choice during the water change that follows an ammonia reading.

How much do I need for a large koi pond?

At 240 ml per 3 600 litres, a 10 000-litre pond takes about 670 ml per dose, so the 1.89 litre bottle is the practical size.

Is API Pond Ammo-Lock available in South Africa?

Yes — Jungle Aquatics in Fourways, Johannesburg stocks the 473 ml and 1.89 litre bottles and delivers nationwide; live pricing and stock are on jungleaquatics.com.

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South Africa's leading pet and aquarium store since 2007 — with the API range on the floor in Fourways, advice from people who test water every day, and easy ordering from anywhere in the country.

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