Blister pack for the JBL PROAQUATEST O2 refill, three numbered reagent bottles 1, 2 and 3

The three bottles of JBL ProAquaTest oxygen O2 reagents supplied in the refill, on a white background

Reagent refill for dissolved oxygen test

Name: Reagent refill for dissolved oxygen test
Brand: JBL
SKU: J2411300
Price: 10.05 USD
Availability: InStock

$10.05

These three bottles are the reagents for the dissolved oxygen test, providing approximately 40 measurements. Each measurement uses 6 drops from each of the three bottles.

The method fixes the oxygen in the test tube at the moment of sampling, then reveals it through a colour reaction. The glass test tube, its screw cap, the syringe, and the colour chart from your kit remain in use throughout.

Ref. J2411300·Reagent refill

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The summary

Three corrosive bottles: the dosed sample never goes back into the fish water; it is tipped down the sink.
What the box contains: 3 reagent bottles numbered 1, 2 and 3.
How many tests: around 40, at 6 drops from each bottle.
Time of measurement: in the early morning in summer, when the curve is at its lowest.
The alert threshold: below 4 mg/L in the early morning, increase the aeration that same day.
Three reagents or the full test: the refill is enough if your test tube still closes without leaking and your colour chart is in shades of red.

Reagents 1, 2 and 3 for the oxygen test, approximately 40 measurements, from 1 to 10 mg/L

These 3 reagents replace those in the O2 dissolved oxygen drop test and give about 40 tests, from 1 to 10 mg/L. They are read against the red-toned colour chart of the current version, using the test tube you already have. Test in the early morning, aim for 5 to 8 mg/L, and pour the sample down the sink, never into the fish's water.

Dissolved oxygen leaves the water as soon as it is poured or stirred, so this test fixes it chemically in the test tube, at the very moment of sampling, before revealing it through a colour. These three bottles, numbered 1, 2 and 3, are the reagents for that step, for about 40 tests between 1 and 10 mg/L.

🧪 Three reagents in order

Fill the test tube to the brim by dipping it into the water, then slowly add 6 drops of reagent 1 and 6 drops of reagent 2, letting it overflow. Close it without trapping any air bubble and shake vigorously for about 30 seconds. Only then add 6 drops of reagent 3, close again and shake for another 30 seconds, as a bubble no longer has any effect at this point. After 10 minutes, hold the test tube on its side and move it back and forth 3 to 5 cm above the white part of the colour chart, whose shades range from yellow to dark red.

🐟 Three consumers of oxygen

Fish are not the only ones breathing in your water: the bacteria in the filter also need oxygen to convert ammonium into nitrate, and the roots of your crops consume it too. In aquaponics, the working range is 5 to 8 mg/L. The amount of oxygen water can hold decreases as the temperature rises, whereas plants, in the light, can push levels 1 to 2 mg/L above saturation by the end of the day. Measure early in the morning, then, when the value is at its lowest, and the guide to looking after your system in summer covers what to do during this period.

An air pump when the morning reading drops

If your morning reading falls below 4 mg/L, a one- or two-outlet aquarium air pump increases gas exchange at the surface, where the water takes up oxygen again. You then take another reading the following morning, at the same time, to check the effect of the aeration. On a pond, the complete pond aerator does the same job over a larger volume.

The three-bottle refill follows the red colour chart

This refill matches the current oxygen test, which uses three reagents and a colour chart in shades of red. An older kit with two reagents came with a colour chart in beige tones, and these new bottles cannot be read against it. Check the colour of your chart before ordering: if it is beige, you need the complete oxygen test.

All three reagents are classified Danger, with the hazard statement H314, which indicates severe skin burns and eye damage. Reagent 1 also carries H373 and H412, and reagent 3 carries H317 and H334, which indicate a risk of skin and respiratory allergy. Work over a sink in a well-ventilated room, keep your face away from a treated test tube, and empty it down the sink, never into the fish water.

📆 40 tests, one complete set

Each test uses 18 drops, 6 from each of the three bottles, which explains the figure of around 40 tests. At the recommended rate, one test a week for a newly filled system and an extra one whenever your fish show signs of oxygen shortage, the kit covers several months of monitoring. Store the three bottles capped, in a dry place at room temperature and in their original packaging, and replace them together, since they run out at the same rate.

Unopened, the three reagents keep for 3 years. They replace those of the current version of the dissolved oxygen drop test, which is read against the colour chart in shades of red. Order the refill before summer, when the early-morning reading becomes most useful, and pour each sample down the sink: these reagents must never go into the fish water.

Technical specifications

What the refill contains

Contents: 3 reagent bottlesReagents 1, 2 and 3, numbered on the label
Readings: Around 40Six drops from each bottle for every measurement, so 18 drops in total
Manufacturer's reference: JBL 2411300, PROAQUATEST rangeNot to be confused with 2411200, which is the complete kit
Matching test: Dissolved oxygen test O2Ref. 2411200, 3-reagent version with a colour chart in shades of red

Reading the oxygen

Reading range: 1 to 10 mg/LOne milligram per litre equals one ppm in fresh water
Target values: 5 to 8 mg/LWorking range in aquaponics. Saturation falls as the water warms up

Hazard labelling

Signal word: DangerThe 3 bottles are sorted
Pictograms: Corrosion and health hazard
Hazard statements: H314, H373, H412, H317, H334H314 on all three, H373 and H412 on reagent 1, H317 and H334 on reagent 3
Precautionary statements: P101, P102, P303+P361+P353, P305+P351+P338, P501
Precautions: Sink, ventilated room, out of reachManganese, sodium hydroxide and sulphuric acid declared
Storage: 3 years, unopened bottlesAll three wear out faster once opened

To allow for in addition

Test tube and screw cap: Those of the oxygen testThe test tube is filled by immersion and closed while overflowing, without trapping any air
Colour chart for reading: The one from the oxygen testThe current colour chart, in shades of red, matches the three reagents

6 further specifications are available in the detailed view.

In the box

3 reagent bottles, numbered 1, 2 and 3

Manufacturer's values (O2 test instructions, safety data sheets and FAQ). Saturation by temperature: table in the instructions. Range of 5 to 8 mg/L: FAO, small-scale aquaponics.

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.

Topping up, or buying the kit again?

Three bottles on one side, the same three bottles plus the glassware on the other. What decides it is the condition of what you keep from one year to the next.

An oxygen measurement depends on airtightness The three reagents will not give an accurate result if the test tube lets a bubble in as it closes, or if the white background of the colour chart has yellowed.

	Reagent bottles (bottles)	Possible tests (tests)	Glass test tube with screw cap	Graduated sampling syringe	Red colour chart with a white section	Price
Recommended Reagent refill for dissolved oxygen testYour choice	3 bottles	40 tests	No	No	No	$10.05
Dissolved oxygen O2 water test in dropsYour choice	3 bottles	40 tests	Yes	Yes	Yes	$16.83

Reagent refill for dissolved oxygen testRecommended

What runs out

Reagent bottles (bottles)3 bottles

Possible tests (tests)40 tests

What keeps

Glass test tube with screw capNo

Graduated sampling syringeNo

Red colour chart with a white sectionNo

Budget

Dissolved oxygen O2 water test in drops

What runs out

Reagent bottles (bottles)3 bottles

Possible tests (tests)40 tests

What keeps

Glass test tube with screw capYes

Graduated sampling syringeYes

Red colour chart with a white sectionYes

Budget

Contents of the two boxes based on the instructions and the data sheet of the oxygen test.

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 is the test tube filled by immersion?

At what time of day should you measure?

Test first thing in the morning, before daybreak if possible. Dissolved oxygen follows a 24-hour curve: its level rises while plants and algae receive light, then falls during the dark, since fish, bacteria and plants all keep respiring.

A reading taken in the middle of the afternoon therefore gives the best value of the day, and tells you nothing about the lowest value, reached before daybreak.

What level can the water reach depending on its temperature?

Temperature	Saturation
10 °C	10.9 mg/L
16 °C	9.6 mg/L
20 °C	8.9 mg/L
24 °C	8.3 mg/L
28 °C	7.8 mg/L

Water at 28 °C therefore cannot exceed 7.8 mg/L without help from the plants, which leaves little margin above 5 mg/L. A well-planted tank can exceed saturation by 1 to 2 mg/L at the end of the lighting period.

What should you do when the morning oxygen level falls below 5 mg/L?

Between 4 and 5 mg/L, increase aeration and keep watching; below 4 mg/L, act within the day. In aquaponics, the recommended level remains above 5 mg/L.

Increase surface agitation, since that is where the water takes up oxygen.
Connect an air pump and a diffuser, or strengthen the ones already running.
Reduce feeding, because the digestion of the fish and the decomposition of leftovers consume oxygen.
Take another reading the next morning, at the same time.

Does a bubble in the test tube skew the reading?

Yes, and it is the most common mistake with this test. A bubble trapped before reagent 3 is added exchanges gas with the water during the first shake, and the value you read comes out higher than the reality. After reagent 3, the oxygen is fixed and a bubble no longer has any effect.

The check takes a glance: before screwing on the cap, look at the test tube from the side; it should be slightly overfull. If a bubble remains, empty it and start again rather than trying to dislodge it by tapping.

What precautions should I take with these three bottles?

All three reagents are classified Danger, with the statement H314: severe skin burns and eye damage. An eye that has been splashed should be rinsed straight away, for several minutes, with the eyelid held open.

Reagent 1 also carries the statements H373 and H412, and reagent 3 the statements H317 and H334, skin and respiratory allergy. Work over a sink in a well-ventilated room, screw the child-resistant caps on fully, and take an empty bottle to a recycling centre with household chemical products.

The dosed water is poured down the sink under running water: loaded with manganese and acid, it must never go into the fish water.

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Reagent refill for dissolved oxygen test

The summary