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JBL PROAQUATEST KH Carbonate hardness
Quick test to determine the carbonate hardness (KH) in freshwater/marine aquariums and ponds

Product information sheet Instructions
  • Simple and reliable monitoring of the water values in aquariums and ponds. Determines the ideal carbonate hardness in fresh and marine water
  • Colour change test: fill plastic cuvette with sample water, add reagent drop by drop until colour changes from blue to yellow. Number of drops = level of carbonate hardness
  • When to use: daily in the first week in newly set up aquariums, afterwards once a week
  • You will find detailed information and troubleshooting tips about water analysis on the JBL website in Essentials/Aquarium or Pond
  • Package contents: 1 KH quick test, incl. one reagent and plastic cuvette. Reagent refill separately available
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Price: 12,16 €
Recommended retail price incl. VAT
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Price: 6,75 €
Recommended retail price incl. VAT
You can find this item in your specialist and online shop
Dealer close to you
Instructions

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Product information

Healthy aquarium/healthy pond with conditions close to nature
The right water values are dependent on the fish stock and the plants in the aquarium/pond. Even if the water looks clear it can be contaminated. With bad values diseases or algae can appear in the aquarium/pond. To maintain a healthy aquarium/pond with conditions close to nature it is important to check and adapt the water values regularly.

For each water analysis JBL provides water tests in the form of quick tests or colour change tests. These determine a certain value or several values in one go. With these water tests you can recognise algae problems and negative nitrate, nitrite, potassium, magnesium values etc.

Why test?
The well-being of aquarium and pond dwellers and the healthy growth of aquatic plants depend to a large extent on the KH level being kept as constant as possible. The carbonate hardness is one of the most important water values since it keeps the pH level stable. The KH should never drop below 4 °dKH.

JBL Online Laboratory
Regular control for a healthy aquarium/pond with conditions close to nature. Enter your water values into the JBL Online Laboratory and get an in-depth analysis of your values within seconds.

Recommended KH values:
Freshwater aquarium (community aquarium): 5-12 °dKH
Lake Malawi/Lake Tanganyika aquarium: 7-20 °dKH
Plant aquarium with few fish (aquascaping): 3-8 °dKH
Marine aquarium: 7-10 °dKH
Pond: 7-10 °dKH

Videos
Details

JBL PROAQUATEST KH Carbonate hardness

Art. no.:
2411000
EAN Code:
4014162241108
For:
Set
Volume packaging:
0.8 l
Gross weight:
88.5 g
Net weight:
51 g
Weight factor:
0
Packaging dimensions (l/h/w):
43/175/106 mm

Properties

Animal species: Armored catfish, Arowana, Axolotl, Barbels, Bettas, Bichirs/reedfish, Blowfish, Catfish, Cichlids (South America), Clawed frogs, Clawed shrimps, Corals, Crayfish, Crustaceans, Danions, Discus, Dwarf crayfish, Dwarf shrimps, Flowerhorn, Gill maggots, Gobies, Goldfish, Gouramis, Guppy, Juvenile fish, Killifish, Livebearers, Loaches, Mussels, Newts, Panchaxes, Rainbowfish, Snails, Spiny eels, Terrapins, Tetra, Tropical terrapin, Veiltails, Water turtles, blood parrot cichlids, freshwater butterflyfish
Animal size: For all animal sizes
Animal age group: All aquarium fish
Material: Reagent(s) in plastic bottle(s) and/or glass bottle(s) + plastic and/or glass accessories. REFILL: reagent(s) without accessories.
Colour: white / transparent / black
Dosage: See instructions

Electronic label / illuminant

Mercury: No
Dimmable: No

Technical Data

Height:175 mm
Length:106 mm
Width:43 mm

JBL PROAQUATEST KH REFILL

Art. no.:
2411100
EAN Code:
4014162241115
For:
Refill
Volume packaging:
0.57 l
Gross weight:
28 g
Net weight:
10 g
Weight factor:
0
Packaging dimensions (l/h/w):
30/175/110 mm

Properties

Animal species: Armored catfish, Arowana, Axolotl, Barbels, Bettas, Bichirs/reedfish, Blowfish, Catfish, Cichlids (South America), Clawed frogs, Clawed shrimps, Corals, Crayfish, Crustaceans, Danions, Discus, Dwarf crayfish, Dwarf shrimps, Flowerhorn, Gill maggots, Gobies, Goldfish, Gouramis, Guppy, Juvenile fish, Killifish, Livebearers, Loaches, Mussels, Newts, Panchaxes, Rainbowfish, Snails, Spiny eels, Terrapins, Tetra, Tropical terrapin, Veiltails, Water turtles, blood parrot cichlids, freshwater butterflyfish
Animal size: For all animal sizes
Animal age group: All aquarium fish
Material: Reagent(s) in plastic bottle(s) and/or glass bottle(s) + plastic and/or glass accessories. REFILL: reagent(s) without accessories.
Colour: white / transparent / black
Dosage: See instructions

Electronic label / illuminant

Mercury: No
Dimmable: No

Technical Data

Height:64 mm
Length:24 mm
Width:24 mm
diameter:24 mm
FAQ
Where can I find the record sheets for the documentation of my water analysis?

Have you lost your record sheets, used them all up, or need them in another language?
In the appendix of this FAQ you will find PDF files for printing them out in German, English and French.

I have lost my colour chart. Can I download the colour chart for the test?

The colour cards are not available for download on the JBL website. The absolutely accurate colour reproduction that is required can only be achieved using a printer which can be re-calibrated before each printout. Most privately used printers are not accurate enough for this.

You will find the colour chart bundle as a spare part on the respective product page and in the spare parts shop under: https://www.jbl.de/en/products/detail/8732/jbl-proaquatest-assortiment-color-chart

Why are there no colour charts for GH. KH, Mg /Ca saltwater and CO2 direct?

The tests from the test range: JBL GH test, JBL KH test, JBL calcium test Ca and JBL magnesium test Mg, where the number of drops are counted until the colour changes and the counted value is multiplied by a value:

GH = number of drops = general hardness in °dH

KH = number of drops = carbonate hardness in °dH

CO2 = number of drops * 2 = CO2 in mg/l

Magnesium + calcium = number of drops * 120 = amount Ca + Mg in mg/l

Calcium = number of drops * 20 = amount Ca in mg/l

Magnesium = amount Ca+Mg from magnesium test - amount Ca in mg/l = magnesium in mg/l

What can I do when the measured value of a water test falls outside the scale?

If one of your measurements reaches the end of the colour chart scale you can multiply the scale by diluting later tests with distilled water (e.g. JBL Dest).

Here’s how to do it: dilute the sample with distilled water and carry out the test once more.

This works in detail as follows:
GH test: Instead of 5 ml use 10 ml aquarium water. Now 1 drop is equivalent to 0.5 dGH.
KH test: Instead of 5 ml use 10 ml aquarium water. Now 1 drop is equivalent to 0.5 dGH.

Note: when using 10 ml sample water the colour development is weaker with the first drops than with 5 ml sample water. Put the measuring container on a white underlay for a better readability.

NH4/NH3 ammonium/ammonia, NO2 nitrite, Fe iron and Cu copper:
2.5 ml sample + 2.5 ml dist. water: result times 2
1 ml sample + 4 ml dist. water: result times 5
0.5 ml sample + 4.5 ml dist. water: result times 10

NO3 nitrate, SiO2 silicate, PO4 phosphate sensitive and Mg magnesium freshwater:
5 ml sample + 5 ml dist. water: result x 2
2 ml sample + 8 ml dist. water: result x 5
1 ml sample + 9 ml dist. water: result x 10

PO4 phosphate koi high range:
2.5 ml sample + 2.5 ml dist. water: result x 2
1 ml sample + 4 ml dist. water: result x 5

K potassium:
7.5 ml sample + 7.5 ml dist. water: result x 2
3 ml sample + 12 ml dist. water: result x 5
1.5 ml sample + 13.5 ml dist. water: result x 10

K potassium in marine water:
1. Fill 10 ml of sample water with distilled water to 300 ml.
2. Follow the instructions for fresh water.
3. Multiply the test result by a factor of 30.

CO2 direct, Ca calcium and Mg+Ca magnesium+calcium: not required.

Do my water tests still work although they have been open for nine months?

Basically a sealed test keeps longer than an open one. How much the shelf life is reduced depends crucially on the handling and the storage conditions of the reagents. It may happen that a reagent in a test that has been open for 9 months doesn’t indicate correctly any more. However, additional information is needed to answer this question properly.

Blog (opinions & experiences)

JBL TV #68 Running-in phase in the aquarium - bacteria, nitrite peak & the first inhabitants

Starting a new aquarium correctly has a significant influence on how it functions afterwards.

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JBL TV #53 How do you carry out water tests correctly and what are the most common mistakes?

Water tests for aquarium water can be very important, especially when there are problems.

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JBL TV #52 What kind of water do my aquarium fish need? What water values are ideal?

We want our aquarium fish to feel comfortable in the water. But what does ideal water mean for fish in the aquarium?

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JBL PROAQUATEST - simple yet laboratory standard - Part II

Today we’re continuing on the topic of water tests, with Part II of the blog post from 22.01.2023. Enjoy reading.

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JBL PROAQUATEST - simple yet laboratory standard - Part I

Aquarium water tests are similar to a blood test at the doctor's. Water tests allow you to take a look at the water composition.

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JBL TV #45: Optimum water values in the freshwater aquarium - 15 parameters explained simply

Biologist Heiko Blessin explains in an easy to follow way what the individual water values mean.

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JBL TV #38: Important for aquarists: pH, KH and CO2 - The correlation between them.

These 3 water values are the most important of all!

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JBL water tests - how to test correctly and reap the benefits

Lots of scientists & experts swear by the JBL water tests, but why?

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JBL TV #27: Testing aquarium water - this is how it works

Water tests for aquariums: Aquarium water can be clear and still toxic to aquarium inhabitants!

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JBL TV #13: What is carbonate hardness? It is the most important water value for your aquarium!

What is carbonate hardness? Why is carbonate hardness like life insurance for your aquarium? What is the difference between it and general hardness and how does carbonate hardness work in your aquarium?

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JBL TV #2: Why do algae grow in the aquarium and how can you stop it?

When algae take over the aquarium, there are always one or two possible causes. In this video, biologist Heiko Blessin explains very clearly and comprehensibly why algae grow at all and what we aquarium enthusiasts can do about it. The topic of algae in the aquarium has never been explained in a simpler and more understandable way!

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Misunderstandings – typical beginner mistakes

Based on our own experience in customer service and the many messages and questions we receive, we have put together the typical mistakes beginners may make. The experienced aquarist might well smile, but if they are honest, these are mistakes we all made at the start, aren’t they?

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Time For A Change - Pros And Cons

Think back to your childhood. Your bedroom was a small area for you to let your imagination run free. And unsurprisingly you felt like re-decorating and rearranging it at least every three weeks.

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How often do you need to test your pond or aquarium water?

Granted, nobody really enjoys testing water. It’s time-consuming and sometimes you’re not sure which colour on the chart your water result matches. But water testing really can be lifesaving – at least for your fish!

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Why is the KH higher than the GH?

Many aquarium owners think that the general hardness represents the total of all minerals and the carbonate hardness only a part of it. Then how can the carbonate hardness sometimes be higher than the total of minerals?

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Testing Water in the Jungle

Our 15 expeditions have taught us something new: In natural waters nitrogens (ammonium/ammonia, nitrite and nitrate) and phosphates are ALWAYS scarce and below the limit of detection. Only when humans have an influence on the natural water, can nitrogens and phosphates be found.

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Seasonal Pond Care

Spring, summer, autumn and winter. For each season there is a different maintenance to follow and various aspects to consider.

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Outline: Fertilisation in the Aquarium

The JBL plant care concept leads to vigorous and healthy growth even with the most demanding aquatic plants. JBL has all the components you need, whether it’s a fertiliser, a bottom substrate or a fully automatic CO2 fertiliser system.

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Carbonate Hardness – The Life Insurance for the Aquarium

The carbonate hardness (not the general hardness!) contains components which stabilize the pH level. They prevent extreme pH levels and ensure the aquarium functions properly.

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Care products - The best solutions for your aquarium

With the right products, aquarium care is not only easy, but can also be a lot of fun! The formulas that make up JBL products are based on intensive research and, especially with care products, their effects are not always immediately visible, yet in the medium and long-term they’ll result in a beautiful aquarium and healthy fish.

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The sensitive KH value in the pond

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Inaccurate water tests – or did I do something wrong after all?

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Testing water – here’s how

The water in your aquarium is outstandingly significant because it is a life-giving element for fish and plants.

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Keeping an eye on the most important water values

Professional water analysis sounds very expensive. But the professional water testing in your aquarium or pond at home also works on a high level and above all it is simple and inexpensive.

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Water values for water plants in detail

If we transfer this Liebig’s Law of the Minimum to the aquatic field it quickly becomes clear how important balanced fertilisation is for plant aquariums.

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Sudden drop in acidity: danger lurks in your pond after heavy rainfalls

Kaum ein Thema ist aktuell präsenter als der starke Regen. Überschwemmungen sind in ganz Deutschland ein Thema. Auch für Ihren Teich bedeutet der Regen eine große Veränderung. Durch die Verdünnung mit Regenwasser sinkt die Karbonathärte des Teichwassers.

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Treating fish diseases before they arise

Even if your fish have fallen ill, it is not too late. Nonetheless we want to save the fish from getting ill. About 90 % of all fish diseases are the result of a weakening of the immune system.

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Press
14.08.2020

JBL has the largest range of water tests worldwide!

With 24 different water analysis tests for freshwater and marine aquariums and ponds as well as 8 different test cases, JBL offers the widest range of water tests worldwide. The second place is shared by two American manufacturers with 15 individual tests each, but with only 0 and 2 test cases respectively.

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12.03.2019

JBL Water Tests Now Even Better

Scientists, aquarium owners, pond enthusiasts, and especially those who need reliable, accurate water tests, use JBL water tests. Over the years, the JBL development team has been collecting and is now ready to implement your suggestions for improvements.

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Reference guide (Themeworld)

Testing water

Water can look crystal clear and still contain a deadly poison such as arsenic. Unfortunately we are unable to assess the quality of the pond water by looking at it.

Rainwater

Rainwater gradually softens your pond water. What consequences does this have for your pond?

Seasonal maintenance

Which seasonal maintenance is needed? What do you need to remember when?

Water maintenance

What does water maintenance involve? Why is it important to look after your pond water?

Fish care

How do you protect your new fish? What to remember when caring for fish?

The water tests – all parameters

You don't always have to do all the tests, any more than your doctor will look in your ears when your knee hurts. In the following table you will find brief information about where a water test can help.

Algae species

Do you have green water or thread algae? We’ll give you long term solutions for algae problems

Pond fish diseases

Which diseases affect pond fish and how can you combat them?

Marine water

There is a solution to almost every problem! And the hardest part is finding the cause of the problem.

Reducing problematic water values

How to lower critical water values.

Diseases

Recognising and treating fish and invertebrate diseases

Deficiency symptoms

Here’s how to prevent deficiency symptoms in fish and plants

Combating algae

Do you have green water or thread algae? We’ll give you long term solutions for algae problems

Algae control

Here’s how to combat algae successfully and lastingly.

Marine water treatment

What maintenance does your marine aquarium need?

Testing water

Testing water – the most important step to understanding your aquarium. Why is water testing necessary?

Fish breeding in aquariums

Would you also like to breed your fish? What do you have to consider when breeding?

Fish species

Which fish species suit your aquarium? What demands do the fish species have?

Invertebrate species

What invertebrate animals are suitable for your aquarium? What demands do invertebrates have? What do you need to consider for their care?

Adding

How to catch fish properly without causing them stress? How to transport and add fish?

Planning and stock

Which fish are compatible? What do you need to consider when selecting fish?

Water tests

What water tests are available? How do water tests work? How do you test properly?

Water values

Which water tests are important? How can you achieve perfect water values?

Plants

Which aquarium plants are best? What’s the best way to plant them?

CO2 plant fertilisation

How important is CO2 plant fertilisation? Why do your plants need additional CO2? How does a CO2 system work?

The marine aquarium

Holiday at the coral reef - in your own living room! Marine aquariums are the most exciting branch of aquatics

Biotope (habitat) aquarium types

A real piece of the Amazon or, with the Congo, a piece of the heart of Africa. A habitat (biotope) aquarium is a challenge. Can you emulate nature?

Aquascaping aquarium type JBL Dreamscape®

Mountains, valleys, meadows and fish! Create your dreamlike landscape under water with the Dreamscape® aquarium

Jungle aquarium type JBL Rio Pantanal®

A bit of jungle river in your living room. Lively underwater action! No problem with the JBL Rio Pantanal® aquarium

Goldfish aquarium type JBL Goldfish Paradise®

Lively goldfish in the aquarium enhance any room perfectly! Invite some new flatmates into your home with this goldfish aquarium.

Rocky reef aquarium type JBL Malawi Rocks®

The fish of Lake Malawi are as colourful as the fish in the coral reefs. This aquarium brings a bit of freshwater reef into your living room

The right filter material

What sort of filter material to choose? What filter material solves which problems? How can you clean it? Where does it need to be positioned in the filter?

Daily care

How much daily or weekly care is involved? What are the basic maintenance measures for your aquarium?

Plant care

What maintenance measures do your aquarium plants need?
Download

Instructions

Additional product information and downloads

spare parts

component set for water tests 
Customer reviews

Reviews

Overall rating: 5.0
7 public review(s) for this product.

0 Reviews

7 more reviews in other languages

7 Reviews in other languages

C. Kischnick - German
2023-12-05T17:03:06Z

Ein super produkt

P. Pfeiffer - German
2023-12-01T15:52:40Z

Ein sehr genauer Test!

Sehr zu empfehlen

dr_scaper - Polish
2023-06-06T22:51:09Z

very professional aquarium test. these are the only tests i trust

T. Fischer - German
2022-09-15T19:01:58Z

Ich brauche diesen Test regelmäßig für die Kontrolle in meinen Sulawesi Becken (Tylomelania Zuchtbecken). Ich kann mich immer auf die Angabe verlassen. Einfach und genau, so muss das sein! Top Refill für meinen Testkoffer :)

G.E.P.P. - French
2022-07-05T07:21:58Z

Idéal pour venir compléter une malette de test.

Carl, GEPP

aquarium.meer91 - German
2021-12-31T20:11:20Z

Ein sehr guter und einfach anzuwendender KH Test.

cichlids_catalunya - Spanish
2021-11-25T10:07:10Z

Genial para medir el KH de nuestros acuarios, 100% fiable

JBL KH - safety information in accordance with GHS

Signal word: Danger

Hazard symbol

  • GHS02
  • GHS05

Risk phrase

H226: Flammable liquid and vapour.
H314: Causes severe skin burns and eye damage.
H318: Causes serious eye damage.

safety note

P101: If medical advice is needed, have product container or label at hand.
P102: Keep out of reach of children.
P303+P361+P353: IF ON SKIN (or hair): Take off immediately all contaminated clothing. Rinse skin with water [or shower].
P305+P351+P338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P501a: Dispose of contents/container in accordance with local regulations.
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