Blister pack of the JBL PROAQUATEST PO4 Sensitive refill, one powder reagent and two bottles of reagent 2

Pot of powder and two bottles of JBL ProAquaTest phosphate PO4 reagents supplied in the refill, on a white background

Reagent refill for phosphate PO4 test

Name: Reagent refill for phosphate PO4 test
Brand: JBL
SKU: J2412800
Price: 1100.0 RSD
Availability: InStock

1,100.00 RSD

366.66 RSD × 3 with no fees Klarna.

These three bottles, including two of reagent 2, are the reagents for the phosphate test, for about 50 tests.

This formulation measures the low end of the scale, from 0.05 to 1.8 mg/L, which is where the recommended thresholds lie. You carry on using the glassware, the syringe, the measuring spoon, the block and the colour chart from your kit.

Ref. J2412800·Reagent refill

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The summary

Reagent 2: corrosive, it is poured over a sink and never goes into the fish water.
What the box contains: 3 bottles, including 2 of reagent 2.
The reading range: from 0.05 to 1.8 mg/L, a formulation that is sensitive at the low end of the scale.
The threshold to keep to: 0.4 mg/L in freshwater, 0.1 mg/L in a garden pond.
What to read it alongside: the nitrate of the same water, on the same day.
Reagents only or complete kit: these bottles are enough if you have kept the double measuring spoon and the colour chart from the kit.

The three reagents for the phosphate test, approximately 50 measurements, from 0.05 mg/L.

This refill replaces the reagents in the Aquarium version, known as Sensitive, of the PO4 phosphate test: one powder and 2 bottles of reagent 2, for around 50 measurements from 0.05 to 1.8 mg/L. Reagent 2 is corrosive and must never go into the fish's water.

In a tank, phosphate comes mainly from fish digestion and uneaten food, and some water companies add it to tap water to protect the pipework. These three bottles, one powder reagent and two bottles of reagent 2, are the reagents alone for the sensitive phosphate test, for around 50 measurements.

This test detects low concentrations, which lets you spot a rise in phosphate before an algae outbreak. Unpolluted natural water contains about 0.01 mg/L, whereas a heavily stocked tank can contain a hundred times more. The guideline is to stay below 0.4 mg/L in freshwater and below 0.1 mg/L in a marine aquarium or a garden pond, three thresholds that fall at the low end of the colour chart, which runs from 0.05 to 1.8 mg/L.

🥄 The small end of the measuring scoop

Fill two 10 ml test tubes, then add to one of them a small level scoop of powder, taken with the narrow end of the double scoop. Close the tube and shake it until completely dissolved, then add 10 drops of reagent 2, mix and leave to stand for 10 minutes. Read the result in the comparator block, next to the untreated tube.

A tube that stays colourless means the wrong end was used

If your test tube stays clear or only faintly yellow even though the water contains phosphate, you have probably measured the powder with the large end of the scoop. The small end is at the place where you would normally hold the spoon, and it is filled level. The same symptom appears with expired reagents.

🐟 Fish ration and growing area

In aquaponics, your plants take up part of the phosphate supplied by the feed, so the reading reflects the balance between the fish ration and the cultivated area. A figure that climbs week after week points first to the ration. The polyphosphates sometimes added to mains water do not show up straight away: the test only detects them once they have hydrolysed into orthophosphates, slowly and depending on the pH. The article on cloudy water in aquaponics sorts out causes that look alike to the eye.

Also test for nitrate when the pond turns green

Add the nitrate test refill at the same time if your tank or pond is turning green. Algae develop when nitrate and phosphate are present together, and the two values taken on the same day show you which one to correct first. On a garden pond, the anti-phosphate treatment comes next if the reading exceeds 0.1 mg/L.

📌 Hazards and storing the bottles

Only reagent 2 is classified, with the Danger signal word and the H314, H302 and H335 statements, as it contains hydrogen chloride. Store the bottles capped, dry, at room temperature and in their original packaging, and open the second bottle of reagent 2 only when the first is empty. Once opened, these reagents degrade faster on contact with air: write the date of opening on the box.

These bottles replace the reagents of the Aquarium version, known as Sensitive, of the phosphate drop test, whose glassware, measuring spoon, block and colour chart you keep; the Koi Pond version uses its own reagents. After reading, the dosed water goes down the sink, never into the fish water.

Technical specifications

What the refill contains

Contents: 3 bottles, including 2 of reagent 2One powder reagent and two bottles of the liquid reagent
Readings: Around 50One small scoop of powder and 10 drops per scoop
Manufacturer's reference: JBL 2412800, PROAQUATEST rangeNot to be confused with 2412700, which is the complete kit
Matching test: PO4 phosphate test, Aquarium versionRef. 2412700, Sensitive formula; the Koi Pond version has its own reagents

Reading phosphate

Measuring range: 0.05 to 1.8 mg/LSensitive formulation, which reads the low end of the scale where the thresholds fall
Recommended levels: 0.4 mg/L in freshwaterIn a garden pond and in seawater, 0.1 mg/L

Hazard labelling

Signal word: DangerReagent 2 only, the powder reagent 1 is not classified
Pictograms: Corrosion and exclamation mark
Hazard statements: H302, H314, H335Harmful if swallowed, causes severe burns, irritates the respiratory tract
Precautionary statements: P101, P102, P303+P361+P353, P305+P351+P338, P501
Precautions: Sink, ventilated room, out of reachHydrogen chloride declared
Storage: Dry, at room temperatureSecond bottle of reagent 2, opened once the first is empty

To allow for in addition

Glassware, syringe and measuring scoop: Those from the phosphate testTwo 10 ml test tubes, and the small end of the double measuring spoon for the powder
Comparator block and colour chart: The ones from the phosphate testSlide the block along the colour chart to match the two shades

6 further specifications are available in the detailed view.

In the box

3 bottles of reagents, including 2 of reagent 2

Manufacturer's values (PO4 Sensitive test instructions, safety data sheets and FAQ). The measuring range matches the test's colour chart.

Manufacturer and product safety

Manufacturer: JBL GmbH & Co. KG
Postal address: Dieselstraße 3, 67141 Neuhofen, Allemagne
Contact: info@jbl.de
Website: www.jbl.de

Information provided under Regulation (EU) 2023/988 on general product safety.

The three bottles, or the phosphate kit?

The same sensitive formulation and the same number of tests are found on both sides. What sets the two boxes apart is the measuring scoop and the reading optics.

The useful thresholds sit in the first third of the colour chart The freshwater threshold is 0.4 mg/L, that of a pond 0.1 mg/L. Precise dosing and low shades that are still legible are therefore essential.

	Reagent bottles (bottles)	Possible tests (tests)	Glass test tubes with screw caps	Graduated sampling syringe	Double measuring scoop for the powder	Grey comparator block	Colour chart for reading	Price
Recommended Reagent refill for phosphate PO4 testYour choice	3 bottles	50 tests	No	No	No	No	No	1,100.00 RSD
Phosphate PO4 water test in dropsYour choice	3 bottles	50 tests	Yes	Yes	Yes	Yes	Yes	2,000.00 RSD

Reagent refill for phosphate PO4 testRecommended

What runs out

Reagent bottles (bottles)3 bottles

Possible tests (tests)50 tests

What keeps

Glass test tubes with screw capsNo

Graduated sampling syringeNo

Double measuring scoop for the powderNo

Grey comparator blockNo

Colour chart for readingNo

Budget

Phosphate PO4 water test in drops

What runs out

Reagent bottles (bottles)3 bottles

Possible tests (tests)50 tests

What keeps

Glass test tubes with screw capsYes

Graduated sampling syringeYes

Double measuring scoop for the powderYes

Grey comparator blockYes

Colour chart for readingYes

Budget

Contents of the two boxes according to the instructions and the phosphate test data sheet.

Estimate your
delivery time

A 0.08 kg parcel, dispatched within 48 hours by Colissimo or Chronopost home delivery, as you choose at checkout. The three bottles are sent in their original packaging. The exact shipping cost is shown in your basket. Once unsealed, this product cannot be returned under the right of withdrawal (article L221-28, 5° of the French Consumer Code), for reasons of hygiene and health protection.

Frequently asked questions

6 questions

6 key questions

Why two bottles of reagent 2?

Can phosphate alone explain an algae outbreak?

Why must the powder be completely dissolved?

A grain left at the bottom does not react, and the colour obtained is then paler than the true value.

On a test where the useful thresholds are measured in tenths of a milligram, this difference is enough to make clean water appear to be what it is not. Cap the test tube, shake until the liquid is clear, and check the bottom against the light before starting the 10-minute wait.

What threshold should I aim for, given my setup?

Your setup	Recommended threshold
Freshwater aquarium	0.4 mg/L
Marine aquarium	0.1 mg/L
Garden pond	0.1 mg/L

These three thresholds all fall within the first third of the reading range, which explains why this sensitive formulation exists.

Where does phosphate in an aquaponic system come from?

Can this test be read on coloured water?

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Reagent refill for phosphate PO4 test

The summary