Heating and cooling

Heating and cooling

The right temperature for your aquarium dwellers

Did you know that most tropical waters are “only“ 25 °C, even when the air temperature is above 30 °C? Only large, slow flowing rivers and lakes are an exception because they are less shaded by trees which means they are heated more by the sun. The oceans, of course, are a world of their own.

Thus most fish and plants are most comfortable in your aquarium at 24-26 °C and only a few fish, such as the discus fish prefer temperatures of nearly 30 °C. Many shrimp species on the other hand prefer cooler water and don’t like hot summers at 28 °C water temperature. They do best when small fans are used to cool the water. ( Cooling ).

Aquarium heaters and aquarium coolers

How to heat and cool your aquarium easily and effectively - What temperatures do our aquarium inhabitants have in their natural habitat? What aquarium heaters are there? Rod heater or external heater - which is better? What are the benefits of undergravel heatings in an aquarium? How can you cool the water in summer? We show you all types of heaters, coolers and thermometers and explain the advantages and disadvantages to you

Heating

Depending on where you live, your room temperature might be below your desired water temperature. Only in summer and in tropical countries is heating not required. Heater thermostats heat up your water to the pre-set water temperature then switch themselves off. This way your required water temperature is constantly maintained.

The heater thermostat

You can, of course, run your tropical fish aquarium without a heater if your room temperature is warm enough to keep the water CONSTANTLY heated at 24-26 °C. Experience tells us that, without a heater, there will be fluctuations in temperature which are not familiar to your aquarium dwellers in their habitat and which they do not like. An automatic heater thermostat will help you to keep the temperature you need at a constant level. Just set the temperature on a dial on the top of the heater and it will always heat whenever the temperature falls below it. Make sure when inserting the heater that there is a good current around it to prevent heat accumulation, which would lead to it switching itself off instead of heating the aquarium. Select your heater to suit your room temperature. The important factors for the choice of heater power are the size of your aquarium and the temperature difference between room and target water temperature, the so-called ∆T. If you have an external filter connected to your aquarium, you would have the option of integrating an external heater ( JBL PROTEMP e300 or JBL PROTEMP e500 ) into the water return hose of your external filter instead of the "disturbance" of a heating rod INSIDE the aquarium.

For larger aquariums from 250 litres upwards experienced aquarium owners use two heaters instead of one, as they only reach the required water temperature together. In the event of a fault (which is very rare – but as with the safety instructions in a plane, we have to draw your attention towards it) one heater is prevented from causing the unwanted death of the fish.

Please don’t select a too strong heater size to be on the “safe side”! This would lead to the switch on and switch off periods of the heater being very short and switching back and forth too often. This permanent on/off behaviour shortens the service life of any heater!

Substrate heater

It is NOT the task of undergravel heating cables to heat up your aquarium water to the desired temperature but solely to create a water circulation inside the substrate to improve the nutrient supply for the plant roots. Thus a substrate heater is a tool for the care of plants (see Substrate ).

Saving energy

An insulation of your aquarium with a foam underlay and possibly also with a thermal insulation on both sides and the rear pane will help you to save energy costs.

Cooling

As already mentioned there are aquarium dwellers, such as shrimps which prefer lower water temperatures of 22-23 °C and tolerate high temperatures of 28 °C only for a short time. But a lot of tropical fish species and aquarium plants in particular also feel uncomfortable at high temperatures. Plant growth can even stagnate noticeably because of too high a temperature! JBL provides you with an inexpensive and effective cooling solution which you can easily install in your aquarium:

Fan units (various lengths available) create an air flow at the water surface which leads to an evaporation cooling process (similar to your sensitivity to the cold when you ride a bike). This way you can reduce the water temperature by approx. 4 °C. With a thermostat ( JBL PROTEMP CoolControl ) you can have your fans switched on automatically in case your set temperature is being exceeded.

Temperature control

With the help of a water thermometer you can easily see what’s happening to the temperature in your aquarium. You can choose between various versions and a thermometer which you can stick to the outside of the glass pane: Thermometers & hydrometers .

JBL PROFLORA CO2 CONTROL
Measurement and control computer for automatic CO2 addition and pH regulation
  • Regulates the addition of CO2 for perfect plant growth in the aquarium and the ideal pH value for aquarium fish
  • Connect temperature sensor, transformer and pH electrode (not included), connect to the solenoid valve, enter the wished pH value or use the automatic programme
  • Touch display enables easy operation through the operating menu. For automatic adjustment of CO2 addition, the carbonate hardness (KH) needs to be measured and entered.
  • The programme calculates the ideal pH value from the KH and the existing pH value and adds as much CO2 as necessary until the pH value is reached. Also displays the water temperature
  • Package contents: CO2 control unit with touch display, wall bracket, power supply unit, temperature sensor + suction holder, connecting cable to the solenoid valve, cuvette holder for calibration liquids
from 287,68 €
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JBL Aquarium Thermometer Float
Aquarium thermometer
  • Precise measurement and healthy fish: glass thermometer for aquariums
  • Easy to install: attach thermometer with suction cup inside the aquarium
  • Marked with the optimum temperature range, floats vertically without attachment
  • Suction holder acid and alkali-resistant
  • Package contents: 1x JBL aquarium thermometer, incl. suction holder
from 3,00 €
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JBL Aquarium Thermometer Slim
Slim glass thermometer for aquariums
  • Precise measurement and healthy fish: high accuracy glass thermometer for aquariums
  • Easy to install: attach thermometer with suction cup in the aquarium, read off temperature
  • 15 cm long glass capillary (very precise reading), made in Germany. Temperature range from 0 - 50 °C
  • Acid and alkali-resistant suction holder
  • Package contents: 1 aquarium thermometer incl. suction cup
from 7,09 €
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JBL Aquarium Thermometer Digital
Digital aquarium thermometer
  • High accuracy of measurement and healthy fish: digital aquarium thermometer
  • Easy to use: attach to the aquarium pane from the outside.
  • Ideal temperature range is labelled
  • Suitable for fresh and saltwater
  • Contents: 1 digital aquarium thermometer
from 4,25 €
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JBL Aquarium Thermometer Mini
Aquarium thermometer
  • Precise measurement for healthy fish: mini thermometer has fine measuring scale with a 2 °C gradation
  • Easy to install: attach with suction cup (also suitable for clamping onto JBL CristalProfi m internal filter)
  • Safe: blue, non-toxic alcohol filling (instead of mercury)
  • Scale from 0 to 50 °C
  • Package contents: aquarium thermometer Mini
from 2,71 €
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JBL Aquarium Thermometer DigiScan
Digital adhering thermometer for aquarium panes
  • Digital aquarium thermometer that displays water temperatures from 0-40 ° C in 0.1 ° C increments
  • To attach: Insert the battery, remove the protective film and simply stick then press the thermometer onto the outside of the cleaned aquarium pane. The 2-part velcro sticker makes the thermometer easy to remove at any time
  • Accuracy: +/- 1.0 °C. Battery: 1 x AG13. Size: 6.5 cm x 5.0 cm. Digit size: 2 cm – easy to read. DO NOT immerse the thermometer in the water! The thickness of the aquarium pane is not a factor
  • The water temperature is very precisely forwarded through the aquarium pane to the temperature contact on the back of the thermometer
  • Package contents: 1digital aquarium thermometer, incl. battery (AG13) and velcro stickers for attachment
from 16,36 €
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JBL Aquarium Thermometer DigiScan Alarm
Digital adhesive thermometer for aquarium panes with alarm function
  • Digital aquarium thermometer that displays water temperatures from 0-37 ° C in 0.1 ° C increments. Preset alarm flashes below18 and from28 ° C
  • To attach: Insert the battery, remove the protective film and simply stick then press the thermometer onto the outside of the clean aquarium pane. The 4-part velcro sticker makes the thermometer easy to remove at any time
  • Accuracy: +/- 1.0 °C. Battery: 1 x AG10. Size: 5 x 3.5 cm. Digit height: 1.8 cm - easy to read. DO NOT immerse the thermometer in the water!
  • The water temperature is very precisely forwarded through the aquarium pane to the temperature contact on the back of the thermometer
  • Package contents: 1digital aquarium thermometer with alarm function, incl. battery (LR1130) and velcro stickers for attachment
from 13,63 €
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JBL PROTEMP e300
External heater for freshwater aquariums from 90 to 300 l
  • In-line heater integrated into the hose of the external aquarium filter, removing the need for a heater INSIDE an Aquarium
  • Easy installation: cut through the hose from the external filter that feeds the water back into the aquarium, insert the external heater in between, insert the plug and set the water temperature you want
  • The integration in the filter circuit ensures a very even distribution of the water temperature with an accuracy of +/- 0.5 °C and a switching interval of 1.0 °C in the aquarium
  • LED display of current and desired temperature. Interchangeable, screw-on (3/4'') hose connections for 12/16, 16/22 and 19/25 mm incl. hose securing. Total length 30.5 cm
  • Package contents: 1 in-line heater 300 W for aquariums from 90-300 l (80-120 cm) with hose connections for 12/16, 16/22 and 19/25 mm and cleaning brush
from 50,30 €
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