JBL Mg Magnesium Test Freshwater
Quick test to determine the magnesium content in freshwater aquariums

  • For the perfect aquarium plant growth: determines the ideal magnesium value to monitor the fertilisation of freshwater aquariums
  • Laboratory comparator system to compensate any inherent water colouring: fill glass vials with sample water, add reagents to another cuvette, place cuvettes in holder, read values on colour chart
  • Use: to set the ideal magnesium content for perfect plant growth, especially for sensitive plants
  • Online Laboratory: free analysis and recommendations for the water values you have measured
  • Package contents: 1 quick test, Mg Magnesium Test Freshwater. Contents for approx. 60 measurements. Incl. 3 reagents, 2 glass vials with screw caps, syringe, comparator block and colour scale. Refill reagents available separately
For more information
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 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?
Along with calcium, magnesium creates the general hardness. Magnesium is, like potassium, a macroelement, which is necessary for healthy and vigorous plant growth. Tap water very often contains too low quantities of magnesium for aquatic plants, quickly causing deficiency symptoms. Despite a regular fertilisation of the aquarium water it can happen that too low quantities of magnesium are available and the plants stagnate in their growth.

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.

Details

JBL Mg Magnesium Freshwater test kit

Art. no.:
2541400
EAN Code:
4014162254146
Content:
60 tests
Volume packaging:
0.800 l
Gross weight:
181.000 g
Net weight:
152 g
Weight factor:
1000
Size(l/h/w):
43/175/105 mm

JBL Mg Magnesium Freshwater reagent

Art. no.:
2541500
EAN Code:
4014162254153
Content:
refill
Volume packaging:
0.450 l
Gross weight:
84.000 g
Net weight:
40 g
Weight factor:
1000
Size(l/h/w):
30/140/107 mm
FAQ
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. For this a guaranteed true colour print is required, and you need 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 spare part on the respective product page and in the spare parts shop.

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 the following 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.

Her’s how in greater detail:
JBL GH test kit: Instead of 5 ml use 10 ml aquarium water. Now 1 drop is equivalent to 0.5 dGH.
JBL KH test kit: 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.

JBL NH4/NH3 Ammonium/Ammonia test kit, JBL NO2 Nitrite test kit, JBL Fe Iron test kit and JBL Cu Copper test kit:
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 test kit, JBL SiO2 Silicate test kit, JBL PO4 Phosphate sensitive test kit and JBL Mg Magnesium test kit 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

JBL PO4 Phosphate test kit 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

JBL K Kalium test kit:
7.5 ml sample + 7.5 ml dist. water: result X 2
3.75 ml sample + 12.25 ml dist. water: result X 5
1.5 ml sample + 14.5 ml dist. water: result X 10

JBL CO2 direct test kit, JBL Ca Calcium test kit and JBL Mg+Ca Magnesium+Calcium test kit:
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.

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Laboratories and calculators

Water Analysis Online Laboratory

Enter your water parameters and get an in-depth analysis of your values in a matter of seconds. You enter your water values – and we analyse! Here you have the opportunity to enter the measured water values directly into the JBL Online Laboratory. This will analyse your values and explain and submit corrective measures.
Worth reading

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

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?

Daily care

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

Fish breeding in aquariums

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

Fertilising

Why do aquarium plants need to be fertilised?

Plant species

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

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?

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Download

Instructions

  • JBL Mg Magnesium Test-Set Suesswasser
    Size:
    1 MByte
    Download

safety instructions

  • JBL Mg Magnesium Test-Set Suesswasser
    Size:
    113 kByte
    Download
  • JBL Mg Magnesium Test-Set Suesswasser Refill
    Size:
    113 kByte
    Download
spare parts
accessories
Safety information
safety information in accordance with GHS
Hazard symbol
  • GHS05
Risk phrase
H314: Causes severe skin burns and eye damage.
safety note
P305+P351+P338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P310: Immediately call a POISON CENTER/doctor.
P101: If medical advice is needed, have product container or label at hand.
P102: Keep out of reach of children.
P103: Read label before use.
P280: Wear protective gloves/protective clothing/eye protection/face protection.
Signal word
Danger