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Aquarium cooling - protect livestock from summer heat

Aquarium cooling - protect livestock from summer heat

The summer can be very stressful for our aquarium fish, shrimp, and aquatic plants. You might think that these creatures, mainly from the tropics, can handle the heat well, but only a few species can withstand water temperatures around 30 degrees for a long time. The ideal temperature for an aquarium is between 22-27 degrees Celsius. Therefore, use a thermometer to determine the water temperature accurately. The aquarium should be heated below and cooled above the recommended temperatures.

It is important to know that the water temperature of an indoor aquarium is always higher than the existing room temperature since the radiant heat of the aquarium lamp raises the water temperature at least by 2-3 degrees °C. Even if it is 26-27 degrees °C inside an apartment on a warm summer day, the water in the aquarium can quickly reach a destructive 30 degrees °C. Our living creatures might tolerate this for a few days, but extreme heat lasting for several days or weeks can be fatal and favor disease or lead to death. In the case of planted aquariums, a lot of attention should be paid to the planting as well. As an example, think of an aquarium with a beautiful green carpet that has carefully been cultivated over months; it can easily succumb after a hot week. So, let's cool the water; therefore, we have many options!

Aquarium cooling fans

Fans can be attached to the edge of the glass and tilted towards the surface of the water at an angle. They blow the water surface, which causes a stronger surface movement and will lead to heat removal. This physical process can cool the aquarium's temperature even below room temperature. The fans are typically equipped with IP splash protection, so they can be used safely near water.

Cooling fans are easy to handle, can be established quickly, and if there's no need for usage, they won't require a lot of storage room. The products aren't dangerous in use; together with a thermostat, they automatically turn off after the desired temperature is reached.

Their disadvantage is that they are a bit noisy (fan sound), and the water evaporation increases during usage. They only operate effectively if the aquarium is open, without water surface coverage.

If you want the temperature to go down 2-3 degrees °C, think of 2 fans per 100 liters!

Aquarium chillers

Aquarium chillers are significantly more professional than the previous solution. There is no need to keep the aquarium and its surface uncovered, and the room temperature doesn't matter in this case. An aquarium chiller almost looks like an external filter. It also operates with an In- and Outlet-System, where the warm water gets transported into the chiller, cools down, and flows back into the aquarium. It's important to know that a chiller won't operate by itself, so either a separate pump must be installed or relate to the external filter cycle (outflowing direction), using the external filter as an engine. Using the external filter as driving power will reduce the flow rate of the external filter unit. Always place a chiller in an area where it can be well ventilated because it produces heat during operation; this should also be considered.

In the case of aquarium chillers, the temperature of the aquarium can be set precisely, no matter how hot the room temperature will be.

It is possible to regulate an aquarium from room temperature to 7-8 degrees °C. An extreme example, but urgently needed by one of our customers, who has a lobster aquarium in his restaurant. For the lobsters, 8-10 degree °C water temperature is ideal.

The above options offer a quick and reassuring solution for reducing water temperature. The product descriptions will assist you in choosing the right cooling product and the perfect size suitable for the needs of your aquarium.

What to do without cooling units – emergency case

  • If the heat hits us unprepared, it is recommended to perform a 30-50% water change every 1-2 days. The water should be slightly colder than the usual setting of an aquarium heater (18-20 degrees °C).
  • Provide more oxygen to the aquarium using an air pump. At higher temperatures, the oxygen level of the water decreases, which can be dangerous for the livestock.
    Please Note: This point is fundamentally correct, but installing an air pump without simultaneously lowering the water temperatures will not achieve the desired effect. Why? The reason is that the oxygen solubility in water steadily decreases as the temperature rises. For example, at a water temperature of 20°C, the maximum oxygen solubility is 8.84 mg/l. At 30°C, the solubility drops to 7.53 mg/l. Therefore, the water temperature is a limiting factor and determines the oxygen uptake capacity of water. Adding more oxygen to the aquarium does not necessarily mean more available oxygen for the livestock. If you want to protect your livestock from oxygen shortages during the hot months, we only can give you one suitable recommendation. Get a cooling fan or unit!
  • Reduce the duration of the light and, if possible, its intensity. 6-7 hours of lighting at a 50-70% intensity rate can help cool down the temperature a few degrees.
  • Leave the top of the aquarium open for better ventilation/temperature exchange.
  • Place a room fan towards the front glass of the aquarium.
  • Although ice cubes usually intended for cooling cocktails can help, neither this nor frozen water bottles can cause substantial cooling in the long term.

Whatever you consider the pointed-out options in an emergency, it shouldn't stay a long-term option. Your livestock will be pleased if you install a cooling fan or system as soon as possible.

Should further questions arise regarding the cooling of an aquarium, we're happy to give more assistance via our customer service.

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