API Microbial Pond Algae Clean — photo 2 of 3

Pond Care

API Microbial Pond Algae Clean

PondBacterial

API Microbial Pond Algae Clean controls green water without a chemical algaecide. It was the first bacterial algaecide registered with the US Environmental Protection Agency, and its patented bacteria target the Chlorella that turns pond water green in koi and goldfish ponds with live plants and fish. As well as controlling the bloom, the bacteria break down dead algae, improve oxygen levels and clear the organic sludge and debris that feed the next bloom. Dose 5 ml per 189 litres twice a week for the first two weeks, then once a week. The 473 ml bottle treats 18 144 litres.

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 Microbial Pond Algae Clean to use for each rate on the pack.

Pond volume

Measured in

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

Standard dose5 ml per 189 litres
Enter a volumeTwice a week for the first 2 weeks, then once a week

A bacterial control — it works with the pond rather than killing the bloom outright.

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	Bacterial pond algae control
Sizes	473 ml · 1.89 L · 3.78 L
Dose	5 ml per 189 litres, twice weekly for 2 weeks, then weekly
Treats	473 ml → 18 144 litres · 1.89 L → 72 576 litres · 3.78 L → 145 152 litres
Controls	Green water algae (Chlorella)
Also does	Breaks down dead algae, removes sludge and debris, improves oxygen levels
Suitable for	Koi and goldfish ponds with live plants and fish
Made by	Mars Fishcare, USA

AlgaeFix or Microbial Algae Clean?

Choose by what is growing and what is living in the pond. AlgaeFix is a chemical algaecide that also handles string algae and blanketweed and acts fast, but it cannot be used where there are shrimp, crabs or crayfish. Microbial Algae Clean is bacterial, targets green water (Chlorella), and additionally digests dead algae and sludge and improves oxygen — a gentler, slower route that suits valuable koi and planted water gardens. For a pond that is green and also full of blanketweed, AlgaeFix does more; for one that goes green every summer, the bacterial route treats the cause. Dose 5 ml per 189 litres twice weekly, then weekly.

Bacteria instead of an algaecide

Rather than killing algae chemically, the patented bacterial culture out-competes and consumes it. That means no sudden die-off of the whole bloom at once, and no chemical residue — which is why it appeals to keepers of valuable koi and heavily planted water gardens.

Cleans up as it clears

The same bacteria break down dead algae and eat the organic sludge and debris on the pond floor, so the nutrients that caused the green water are removed rather than recycled. Oxygen levels improve as the organic load drops.

Twice a week, then weekly

Dose 5 ml — a teaspoon — for every 189 litres, twice a week for the first two weeks to establish the culture, then once a week to hold green water at bay. The three bottle sizes treat 18 144, 72 576 and 145 152 litres in total, so even a large koi pond has a practical option.

Frequently asked questions

What kind of algae does it control?

Green water algae — Chlorella — in koi and goldfish ponds with live plants and fish. For string algae and blanketweed, AlgaeFix is the labelled product.

Will it harm my fish or plants?

No. API states it will not harm plants or fish; it is a bacterial product dosed by pond volume.

How long does a bottle last?

The 473 ml bottle treats 18 144 litres in total, the 1.89 litre bottle 72 576 litres and the 3.78 litre bottle 145 152 litres — several seasons of weekly dosing on a typical garden pond.

Does it help with sludge?

Yes. The bacteria break down dead algae and eliminate organic sludge and debris, which also improves oxygen levels in the pond.

Is API Microbial Pond Algae Clean available in South Africa?

Yes — Jungle Aquatics in Fourways, Johannesburg stocks all three sizes and delivers nationwide; live pricing and stock are on jungleaquatics.com.

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