What Temperature Is Good for Freshwater Tropical Fish?

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So you've started a freshwater tropical fish aquarium. The decor is perfect, the water has been de-chlorinated and you're ready to buy some fish. Have you checked the temperature of your aquarium water? For most fish, the average temperature for freshwater aquariums is 77 degrees Fahrenheit. However, ideal tropical fish temperature varies between species.


Have you checked the temperature of your aquarium water?
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If you add new fish and aquatic plants to an aquarium that is too cold, or too warm, your aquarium is less likely to thrive. Regular maintenance of aquarium water, including close attention to water temperature, will ensure that your freshwater tropical fish stay healthy.

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Ideal tropical fish temperature

Freshwater tropical aquariums should be kept at approximately 77 degrees Fahrenheit for optimal fish health. Although tropical fish can survive in water ranging from 73 to 82 degrees Fahrenheit, it is best to hover around the 77 degree mark if you have a variety of freshwater tropical fish species in one tank.


Precise tropical fish temperature depends on the species of fish you have in your hobby aquarium. Single species tanks should have a narrower temperature range appropriate for that species. Neon tetras, for example, prefer temperatures between 76 and 78 degrees Fahrenheit and become stressed at 80 degrees. Angel fish prefer 75 degrees Fahrenheit or slightly higher. Cichlids thrive in a 75 to 80 degree Fahrenheit range.


Measuring tropical fish water temp

There are a few ways to keep track of the water temperature in your freshwater aquarium. Floating thermometers roam the tank, giving a constant reading. Adhesive thermometers can be placed on the glass front of the aquarium for easy reading. Submersible thermometers may be suction cupped to the interior glass wall of the fish tank.


Whichever thermometer you use to measure tropical fish temperature, make sure it's not placed in an area that might be affected by sunlight. If the thermometer is warmed by the sun on a daily basis, you won't get accurate water temperature results. Also avoid placing an aquarium near a window or door, where drafts can also affect the water temperature.


Heaters for topical aquariums

Keeping your aquarium water warm enough for freshwater tropical fish is not difficult. The use of a special aquarium heater, either submerged into the water or hanging on the edge of the tank, should do the trick. Heaters are rated on their heat output, and sold according to the size of aquarium they need to heat. When purchasing an aquarium heater, be aware of the size of the aquarium it will be placed in.


Do not place your tropical aquarium in the sun to warm the water. The excessive exposure to sunlight will increase the amount of algae growth in the fish tank. Also, the sun cannot be regulated, and the water may get too warm, too quickly, and kill the fish or plants inside.

Correct tropical fish water temp

Tropical fish aquariums that have water at the proper temperature will have clear water and be less likely to grow algae. The water shouldn't feel hot to the touch or have ice on top. The fish and plants should be thriving and moving about normally. For optimal aquarium success, research the temperature requirements of specific fish species in your tank, and combine only those compatible in both demeanor and temperature requirements.



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