JBL hydrometer + thermometer + measuring vessel
Hydrometer for saltwater aquariums

  • Suitable for use in scientific contexts: hydrometer with stable stand, thermometer and measuring vessel
  • Convenient to use: half fill the measuring vessel with saltwater, insert the clean hydrometer, read off values after 1 minute.
  • Reading accuracy of 0.0005 units.
  • Thermometer and built-in temperature correction scale, transport cylinder (height 33.5 cm) serves as measuring vessel
  • Package contents: 1 density measurement device for saltwater, hydrometer with thermometer + measuring vessel
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Recommended retail price incl. VAT
Available from your specialist dealer.
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Product information

Nature at Home – Home for Fish and Plants
Lesser animals and corals need to feel as much at home in the aquarium as they do in the wild. Convert your aquarium water into biotope water and protect these animals by using natural substances.

Density in saltwater aquarium
When aquarium water evaporates salts remain, which increase the density in the aquarium. To prevent damage to fish and plants it is important to check the density regularly and to take any appropriate steps.

Suitable for use in scientific contexts
The JBL hydrometer has a reading accuracy of 0.0005 units. Its octagonal stand makes it stable and it is screwed onto the vessel. The hydrometer has an integrated thermometer and a temperature correction scale.


JBL hydrometer + thermometer + measuring vessel

Art. no.:
EAN Code:
24,5 cm
Volume packaging:
1.840 l
Gross weight:
180.000 g
Net weight:
120 g
Weight factor:
75/390/70 mm
The hydrometer is broken. It contains a red liquid. What does the red liquid consist of and is it toxic?

The hydrometer doesn’t contain any mercury. The liquid contains an alcohol solution with colouring. It is non-toxic. Both ingredients are quickly broken down by the bacteria in the aquarium. Furthermore the diluting effect should be taken into consideration. The silvery pearls are an iron compound and are therefore harmless. Simply siphon them out of the aquarium.

What range does the scale of the hydrometer cover?

A reading accuracy of 0.0005 units makes the hydrometer very accurate.
The built-in thermometer, which covers a scale from 9°C to 32°C, and the temperature correction scale gives you the highest precision. The density is determined in a range of 1016 to 1028.

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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

Setting up a saltwater aquarium

You will find ideas and help for all questions related to your aquarium here, no matter if it’s about fish diseases, water analysis or how to set up an aquarium. You will also find the latest trends and activities which could be important for you.

Solving algae problems in saltwater

Algae belong to a seawater biotope as much as corals do. Only when algae start to take the upper hand do measures need to be taken against them. Because marine algae are very varied, it is best to explain how to deal with the individual marine algae.

Optimising water values

Having the correct water values guarantees you a functioning and beautiful marine aquarium. We’ll show you how to get them.

safety instructions

  • safety instruction for accessories
    17 kByte