Thermostat to regulate 12 V cooling fans for aquariums

  • Automatic activation of the cooling fan when a set temperature between 18 and 36 °C is exceeded (for all JBL Cooler cooling fans)
  • Simple installation: plug JBL CoolControl connection cable into the JBL Cooler. Plug the power supply unit of the JBL Cooler into the JBL CoolControl. Select temperature and switch on
  • Temperature setting wheel from 18-36 °C, function control diode, temperature sensor for measuring the water temperature, DC 5/2 mm plug
  • Switch for Automatic, Manual or Off, operating voltage, function control diode, 12 V DC over power supply of the cooling fan
  • Package contents: thermostat with temperature sensor and 132 cm connection cable to the JBL Cooler, suction holder for temperature sensor (90 cm cable) and double-sided adhesive tape for attachment
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Price: 35,41 €
Recommended retail price incl. VAT
You can find this item in your specialist and online shop
Product information

Temperature control
There are two important factors which affect the water temperature in the aquarium: firstly the room temperature and secondly direct sunlight. If the room temperature in summer increases significantly, it is important to check the temperature in the aquarium regularly. It should be 24-26 °C. Temperatures above 30 °C are a problem and can cause substantial damage to fish and plants. Furthermore aquariums should never be exposed to direct sunlight. The higher the temperature, the less effectively the oxygen, which is vital for the animals, dissolves.

Easy to install
The bracket of the cooling fan is placed onto the aquarium rim (up to max. 2.4 cm thickness) and fixed with clamp screws.

Cools by evaporation
The JBL coolers for freshwater and marine aquariums cool between 2-4 °C with the help of cross-flow fans. Due to the air flow the warm water evaporates at the water surface and thus generates evaporative cooling. This is comparable to evaporation cooling a wet body part exposed to the wind.

Temperature control:
By expanding a JBL ProTemp Cooler with the JBL ProTemp CoolControl, the cooler can be switched on automatically if the set temperature at the CoolControl between 18 and 36 °C is exceeded. Once the temperature reduction has been reached or exceeded, the cooler switches off again.

The water cooler has a safety cover grid and is operated with a low voltage of 12 V.



Art. no.:
EAN Code:
12 V
alle JBL Cooler
Volume packaging:
0.47 l
Gross weight:
113 g
Net weight:
84 g
Weight factor:
Packaging dimensions (l/h/w):
35/183/73 mm


Animal species: Arowana, Artemia, Axolotl, Barbels, Bettas, Bichirs/reedfish, Blowfish, Catfish, Cichlids (South America), Corals, Crayfish, Danions, Discus, Dwarf shrimps, Flowerhorn, Gobies, Goldfish, Gouramis, Guppy, Juvenile fish, Killifish, Livebearers, Loaches, Newts, Panchaxes, Rainbowfish, Snails, Spiny eels, Tetra, Veiltails, freshwater butterflyfish
Animal size: For all animal sizes
Animal age group: All aquarium and terrarium animals
Material: plastic (ABS) / metal
Colour: dark grey

Electronic label / illuminant

Mercury: No
Dimmable: No

Technical Data

Can I operate two coolers with one ProTemp CoolControl?

The ProTemp CoolControl is connected between the power supply and the ProTemp Cooler. It is therefore not possible to connect two coolers to one controller. Each Cooler needs its own controller.

Can the new ProTemp CoolControl also regulate the old Cooler 100-300?

Yes, the new ProTemp CoolControl can also control the aquarium coolers of the previous Cooler 100-300 range.

The cooler does not cool down the aquarium

JBL ProTemp Coolers cool the water temperature by 2-4 °C in high ambient temperatures. To achieve this with this product, it’s important the maximum recommended aquarium volume is adhered to. Please note that the cooling effect only occurs when the cooler is in operation and that the system needs to have been running continuously for a few hours beforehand. The air flow needs to be directed across the entire width of the aquarium and be at a 45° angle to the water surface. If only a part of the water surface is ventilated or the angle is set to 90°, the desired effect will be lost or greatly reduced. The housing can be rotated 360°.

Does my CoolControl work with every aquarium aerator/cooler?

The JBL PROTEMP CoolControl was designed for use with the JBL PROTEMP Cooler, and they work together perfectly. Due to different voltages, flawless function cannot be guaranteed for use with appliances from other manufacturers. Even the connecting plug, which looks identical at first glance, may be a different strength. As a result, a cooler from a different manufacturer may cause unwanted switching, leading to noises in the relay.

Blog (opinions & experiences)

Take part in the JBL Beach Party competition 2023

The last warm days of summer are coming to an end. Take part now and make sure of your chance to win a COOL pack for your aquarium.

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Summer heat - But not in the aquarium, please!

If you own an aquarium you’ll be asking yourself what effects the heat has on your aquarium and on your fish. We’ll tell you and explain what to do.

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JBL TV #54 The right water temperature – all the facts about temperature in the aquarium

A conversation with the chief biologist of the Sealife Centre in Speyer about issues which can arise in some water temperatures.

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JBL TV #49: Saving energy in the aquarium - reducing costs made easy

Yes, we can make energy savings in our aquarium, but not where most people think! In this video we show exactly where and how to save electricity costs.

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JBL TV #48: Fish also need to breathe - measuring and increasing the oxygen content (O2)

Many plants, high temperatures or the use of medicines and anti-algae agents can quickly become a problem.

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JBL TV #41: Heat wave in the aquarium: The effective and inexpensive method for cooling the water

When the aquarium water temperatures are heading towards 30 °C in summer, it’s high time to add a cooling system.

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Control unit for the Aquarium Cooler JBL PROTEMP x200/x300

The JBL PROTEMP CoolControl is a small and very practical device for regulating JBL Coolers.

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Tips for cooling the aquarium - lowering the temperature

How do high temperatures affect our aquarium fish? And what can you do about it? Let us tell you!

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JBL TV #24: Aquarium heaters and aquarium coolers

What temperatures do our aquarium inhabitants have in the wild? How can you heat and cool your aquarium simply and effectively?

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Caution, Summer Heat! A Reason for Scaremongering?

You can’t prevent the temperature in your aquarium from rising. No matter what measures you take your living room will warm up on hot summer days and can even go over 30° C. So what can you do?

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Cooling Aquariums – Summer Heat in Aquariums

Summer means sweat, because even within our homes the temperature rises steadily. This can also be discerned in the aquarium.

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Display Accuracy vs. Measuring Accuracy - Different Results When Measuring Temperatures

You may find the differences that can arise when measuring the temperature with different measuring instruments and methods, confusing. Most people tend to trust a digital device more than an analog device. Is this justified?

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New JBL Cooler: Cross-Flow Fans Are Simply Better

JBL is launching a new generation of fans to cool your aquarium. The new JBL ProTemp Coolers are smoother running cross-flow fans, which send a wide and even air flow over the water surface and use evaporative cooling to lower the water temperature by up to 4 °C.

Find out more
Reference guide (Themeworld)

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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.

Aquascaping aquarium type JBL Dreamscape®

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Heating and cooling

Why is 25 °C ideal? This is how to heat or cool aquarium water


safety instructions

  • safety instruction for technical devices
    • Filename:
Customer reviews


Overall rating: 4.8
17 public review(s) for this product.

1 Review


Excellent, Worth every penny!

I have used this product within the summer and I have to say, that it managed to beat the heat! My tank's temperature was controlled in low levels 20-23 even though the rooms temperature was 30-32! You can check a review of this product on my instagram account " nemophilist_scaper "

16 more reviews in other languages

16 Reviews in other languages

_mister_krabss_ - German

SauerlaenderWelskeller - German

Bei uns läuft der Pro Temp Cool Control Thermostat zusammen mit dem Pro Temp Cooler x300. Wir sind sehr zufrieden. Beides erfüllt seinen Zweck und kühlt das Becken gut herunter. Die Temperaturmessung ist sehr genau möglich. Wir werden beides auch im nächsten Sommer wieder im Einsatz haben.

tefanDerksS - Dutch

Werkt super in samenwerking met de cooler! Een echte aanrader

S. Tejera Galindo - Spanish

El sensor de temperatura es muy efectivo y combinado con el ventilador, hace que la temperatura del agua se nivele hasta los valores deseados.

https://www.tiktok.com/@acuariomania - Spanish

Junto con los ventiladores, una precisión perfecta para mantener nuestros acuarios en su temperatura cuando hace mucha calor en el exterior.

A. Valais - German

Ist ganz gut nur nicht sehr genau 1-2 Grad Ungenauigkeiten aber ansonsten echt gut und auf die 1-2 Grad kommt es auch nicht so drauf an

C. Tsotsoglou - German

Das Thermostat ist etwas ungenau und geht die ganze Zeit an und aus .

Ansonsten tut es seine Arbeit.

Malawi-Cichliden-Portal - German

Bei mir Läuft der PROTEMP CoolControl zusammen mit dem JBL PROTEMP Cooler x300 (Gen 2) sowie JBL PROTEMP Cooler x200 (Gen 2), ich bin sehr Zufrieden, es Läuft beides ohne Probleme und ist sehr Leise. Daumen hoch und sehr zu Empfehlen.

malawireef - French

Hatte probleme im Sommer mein Becken zu kühlen habe mir dann diesen Cooler geholt! Läuft ohne Probleme Installation auch ganz leicht!

bennys riff welt - German

Ich habe den JBL PROTEMP CoolControl zusammen mit dem JBL PROTEMP Cooler x300 (Gen 2). Traumhaft. Es läuft beides 1 A und auch Super Leise. Echt zu Empfehlen

cichlids_catalunya - Spanish

Un qparato increíble, tiene una sensivilidad muy buena y efectiva, muy muy fácil de usar

aquaboxx - German

Meiner Meinung nach ein absolutes Must have für den Kühler von JBL! Einfach praktisch den Kühler immer angeschlossen lassen zu können und das automatisch bei bedarf gekühlt wird! Sehr präzise temperaturmessung. Bin sehr zufrieden

aqua_aktiv - German

Ich gebe dem produkt eine 3.5 weil man es nicht vernünftig oder nur sehr erschwert bei aquarien nutzen kann die zu hoch sind weil es dan dirket hinterm becken steht bzw hängt

Thomas_aquascapingcz - Czech

bez tohoto výrobku bych se vůbec neobešel!! Mám ho zapojený s cooler x200 gen.2 a krásně mi hlídá teplotu vody. Vždy když se zvýší teplota vody tak se zapne chlazení.

exotic_hive - German

Erstaunlich genaue Messung der Temperagtur uns zuverlässige An-Ab-Schaltung.

Lehrkraft - German

Der Controller regelt den Lüfter problemlos. Durch das enthaltene Thermostat gab es in meinem Becken nahezu keine Temperaturschwankungen mehr. Die Verarbeitung ist gut und die Anleitung ebenfalls.

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