Water Conditioners & pH

API Ammo Lock

Freshwater & marineEmergency use

API Ammo Lock is the emergency response to an ammonia reading. It converts free ammonia into a non-toxic form within moments, so fish stop suffering gill damage while the biological filter catches up and removes it in the normal way. It also neutralises chlorine and chloramine, which makes it a useful conditioner for the water change you should do first. Dose 5 ml per 38 litres and repeat every two days until the test kit no longer detects ammonia. It works in freshwater and saltwater aquariums and comes in 118 ml and 237 ml bottles.

Size: 118 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 aquarium volume and the calculator works out how much API Ammo Lock to use for each rate on the pack.

Aquarium volume

Measured in

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

Ammonia treatment5 ml per 38 litres
Enter a volumeEvery two days until ammonia is no longer detected

Do a partial water change before the first dose, then dose the full tank volume.

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 ammonia detoxifier and dechlorinator
Sizes	118 ml · 237 ml
Dose	5 ml per 38 litres, every two days until ammonia is no longer detected
Treats	118 ml → 870 litres · 237 ml → 1 778 litres
Removes	Ammonia (detoxified), chlorine, chloramine
Suitable for	Freshwater and saltwater aquariums
Water change needed	Yes — do a partial change before the first dose
Made by	Mars Fishcare, USA

Ammo Lock treats the symptom; find the cause of the ammonia — overfeeding, overstocking, a dead fish or a damaged filter — at the same time.

My test shows ammonia — what do I do?

First change 25 – 50% of the water, conditioning the new water as you go. Then dose Ammo Lock at 5 ml for every 38 litres of tank volume — about 26 ml on a 200-litre tank. Retest the next day and dose again every two days until ammonia reads zero. Stop feeding for a day or two, check the filter is running and has not been over-cleaned, and look for anything decaying. If the tank is new, add Quick Start so the bacteria that consume ammonia establish faster. A 118 ml bottle treats 870 litres, which covers a full course on most home tanks.

Stops ammonia hurting fish while the filter catches up

Ammonia burns gill tissue at levels a test kit reads as low, which is why fish gasp at the surface during a spike. Ammo Lock binds the ammonia into a form that is harmless to fish yet still available to the nitrifying bacteria, so the tank cycles through it rather than simply masking the problem.

Water change first, then dose

The label is clear: if the tank tests positive for ammonia, do a partial water change before adding Ammo Lock. The change removes a share of the ammonia outright; the treatment detoxifies what remains. Keep testing and repeat the dose every two days until the reading returns to zero.

Dechlorinates the replacement water

Ammo Lock removes chlorine and chloramine, so the water you add during the spike can be treated with the same bottle. Chloramine is relevant here because neutralising it releases ammonia — which Ammo Lock then binds.

Frequently asked questions

Will my ammonia test still show a reading after using Ammo Lock?

API states its ammonia test kits are formulated to reflect Ammo Lock treatment, so you can track the reduction with the same kit. Keep testing every day or two until it reads zero and the filter has caught up.

Does Ammo Lock work in saltwater?

Yes. It is effective in both freshwater and saltwater aquariums at the same dose.

Does it get rid of the ammonia smell?

Not directly. It detoxifies ammonia to protect fish and their gills, but it does not eliminate odours; those fade as the filter removes the bound ammonia and the cause is fixed.

How is Ammo Lock different from Aqua Essential?

Ammo Lock is the dedicated, higher-strength ammonia detoxifier for an active spike; Aqua Essential is an everyday conditioner that also binds ammonia, nitrite and nitrate at its treatment dose. Keep Ammo Lock for emergencies.

Is API Ammo Lock available in South Africa?

Yes — Jungle Aquatics in Fourways, Johannesburg stocks the 118 ml and 237 ml 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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