JBL PROAQUATEST Mg Magnesium Fresh water
Quick test to determine the magnesium content in freshwater aquariums

  • For perfect aquarium plant growth: determines the ideal magnesium value to monitor the fertilisation of freshwater aquariums
  • Laboratory comparator system to compensate the inherent water colour: fill glass vials with sample water, add reagents to one vial, place vials in holder, read values off colour chart
  • Magnesium deficiency in aquatic plants leads to stagnant growth and light leaf colour. Remedy: Increase magnesium-containing fertiliser: JBL Ferropol, JBL ProScape Mg Macroelements
  • You will find detailed information and troubleshooting tips about water analysis on the JBL website in Essentials/Aquarium or Pond
  • Package contents: 1 Mg test kit for approx. 60 measurements, incl. 3 reagents, 2 glass vials with screw caps, syringe, comparator block and colour scale. Reagent refill separately available
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Recommended retail price incl. VAT
Available from your specialist dealer.
Dealer close to you
You can find this article at your specialist shop and online
Recommended retail price incl. VAT
Available from your specialist dealer.
Dealer close to you
You can find this article at your specialist shop and online
Product information

Healthy aquariums with conditions close to nature
The right water values are dependent on the fish stock and the plants in the aquarium. Even if the water looks clear it can be contaminated. With bad values diseases or algae can appear in the aquarium. To maintain a healthy aquarium 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 rapid 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?
Along with calcium, magnesium creates the general hardness. Magnesium is, like potassium, a macro-element, which is necessary for healthy and vigorous growth in plants. Tap water very often contains too low quantities of magnesium for aquatic plants, quickly causing deficiency symptoms. Even if you fertilise the aquarium water regularly, there may still be too low quantities of magnesium available and the plant growth will then stagnate.

Recommended magnesium values:
Freshwater aquarium (community aquarium): 5-10 mg/l
Lake Malawi/Lake Tanganyika aquarium: 5-10 mg/l
Plant aquarium with few fish (aquascaping): 5-10 mg/l
Marine water aquarium: this test is not suitable since the magnesium content in marine water lies at 1200-1600 mg/l. Therefore for marine water use the dedicated JBL Magnesium/Calcium Test.

You can analyse the water values you have measured in the JBL Online Laboratory free of charge and receive recommendations.

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Details

JBL PROAQUATEST Mg Magnesium Fresh water

Art. no.:
2414200
EAN Code:
4014162241429
For:
60 Tests
Volume packaging:
0.800 l
Gross weight:
165.000 g
Net weight:
108 g
Weight factor:
0
Packaging dimensions (l/h/w):
43/175/106 mm

Technical Data

Height:175 mm
Length:105 mm
Width:43 mm

JBL PROAQUATEST Mg Magnesium Fresh water REFILL

Art. no.:
2414300
EAN Code:
4014162241436
For:
Refill
Volume packaging:
0.570 l
Gross weight:
69.000 g
Net weight:
31 g
Weight factor:
0
Packaging dimensions (l/h/w):
30/175/110 mm

Technical Data

Height:64 mm
Length:72 mm
Width: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

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.

The instructions point out that the comparator block should be used to compare the colours. Can this be done without the comparator block as well ? Or is there a factor from this comparison that is required for the measurement ?

The colour charts are intended to be used with the comparator block. In addition, when the comparator block is used with the blank water sample, this compensates the inherent water colour.

Therefore, if the comparator block is not used, there will most likely be deviations in the readings.

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 #8: Do the plants in your aquarium grow exactly as you want them to?

What makes for ideal plant growth? All the factors for good plant growth: light, LED, tubes, fertilisation, fertilisation quantity, fertilisation monitoring, influence of water conditioners, chelated iron.

Find out more

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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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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Plant Fertilisation with Optimised Consumption

The first step shows you how to achieve perfect water values and the second one how to modify your re-dosing to suit consumption. Unlike with standard fertilisation you adjust the fertiliser amount to your aquarium and not only save money but also get perfect looking plants.

Find out more

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.

Find out more

Laboratory Comparator System to Compensate the Intrinsic Colour of the Water

Instead of comparing the colour change of the water on a colour scale, a second measuring glass with the aquarium water is put on the colour field of the colour chart.

Find out more

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 JBL Calculators – Calculated Success

The three most important factors for your plant aquariums are the nutrient balance, the substrate and the lighting.

Find out more

How often should you fertilise – daily or weekly?

The subjects of plant care and fertilisation can sometimes take on a philosophical element. There are a lot of approaches and a lot of them can lead to success. It is important that your chosen approach suits your aquarium.

Find out more

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

In the aquarium scene we often hear people talking about “accurate” and “inaccurate” tests. But mostly they mean a rougher or finer scaling of the output values.

Find out more

Testing water – here’s how

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

Find out more

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.

Find out more

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.

Find out more

Plant care: How can water tests help?

Ideally water looks crystal-clear, yet pollutants are often invisible. That’s why clear water might still be toxic.

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There’s more to fertilization than you’d think Part 2

Simply put, Liebig’s Law of the Minimum states that the growth of plants is limited by the scarcest resource. Adding a nutrient which already exists in abundance does not influence the growth.

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Fertilization is not just fertilization Part 1

Unlike in natural waters, aquariums with fish mostly have a surplus of nutrients caused by feeding and the resulting fish excrement. Thus nitrates and phosphates in large (often too large!) quantities are available for the plants.

Find out more

You ask, we answer: What’s the best way to fertilise an aquascape?

Dear Chris, dear Community, Thank you for your question. A luxuriant plant growth is based on the elements lighting, CO2 supply and an optimal fertilisation with nutrients.

Find out more
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.

Find out more

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.

Find out more
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.

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.

Diseases

Recognising and treating fish and invertebrate diseases

Deficiency symptoms

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

Algae control

Here’s how to combat algae successfully and lastingly.

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?

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?

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

Plant species

Which plant species suit your aquarium? What demands do the individual species have?

Fertilising

Why do aquarium plants need to be fertilised?

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?

Plant growth

Are your aquarium plants growing as well you want? Here’s how to achieve perfect plant growth
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Instructions

  • JBL PROAQUATEST Mg Magnesium Fresh waterV01
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Additional product information and downloads

  • JBL ProAquaTest Mg Magnesium Fresh water
    Download

safety instructions

  • JBL ProAquaTest Mg Magnesium Fresh water
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spare parts
Safety information
JBL Mg Fresh water 2 - safety information in accordance with GHS
Signal word
Danger
Hazard symbol
  • GHS05
Risk phrase
H314: Causes severe skin burns and 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/regional/national/international regulations.
Hazard-determining component
1310-73-2: sodium hydroxide

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