Fish are awesome pets to have but can be super sensitive when it comes to changes in their environment. A drastic change in anything such as water values or even temperature can be stressful enough to cause extreme illness or even death.
The temperature of a fish tank should remain constant, within a couple of degrees at any time. All fish prefer a different temperature some requiring cooler water while others prefer the higher, warmer temps in the low eighties. Regardless of what the recommended temperature is for your particular fish, the most important thing to remember is that it must stay constant.
At times we may find that the temperature of the water will need to be changed. This may be due to equipment malfunction or even home temperature changes. As frustrating as it can be, equipment fails. Aquarium heaters are just like any other piece of equipment and will eventually need to be replaced. However, we may find that even with careful monitoring, the heater may fail causing either a spike or drop in temperature.
In these cases, it is important to replace the heater with a new good quality heater. Heaters found on the market today can typically be set up and be ready to use within minutes. Carefully read over the instructions for any new piece of equipment that your purchase for your fish tank prior to installing it.
In some climates, the temperature of your home may affect the temperature of your fish tank. In extreme warm, and even cold climates we can see a change in the water temperature regardless of whether or not there are heaters or even chillers in use in the tank.
In the end it doesn’t matter why the temperature has changed, what matters is that we get those numbers back to normal so that our fish can remain healthy and happy and in an environment that suits them.
Tank Water is Too Hot
It’s a good practice to check the thermometer every day to ensure there are no drastic changes. An increase in the home temperature or even a heater malfunction can cause a spike in the tank water temperature as well. Because excess heat can cause extreme stress on fish, particularly cooler water fish it is important to gradually get the water back to a more appropriate temperature.
Partial water changes are the best way to take warm water and make it cooler. However, always remember that when it comes to temperature changes, gradual is always best! Never swap out most of the warm water for cool or cold water. While the cool water might be the right temperature, the drastic change alone can be enough to kill a fish.
Do multiple partial water changes over the course of the day to gradually decrease the temperature. Each water change should remove about fifteen to twenty percent of tank water and be replaced with water that is only a few degrees cooler than the water that was removed.
Cooling down a tank is much more difficult and time consuming than warming one, however it can be done with a little bit of patience and effort.
Tank Water is Too Cold
Tank water that is too cold can cause fish to become stressed, ill and sluggish. As mentioned earlier, a gradual increase in temperature is the way to go. If the decrease is due to a failing heater, it should be promptly replaced with a new model. A new heater can be installed, with the appropriate temperature set without much delay. Newer heaters are made to gradually increase the water temperature so that drastic changes can be avoided.
If the heater appears to be working normally, but there is still a drop in temperature you can also try some partial water changes to give the tank a slight temperature increase.
The general rule is that typically a slight decrease in temperature is less hazardous as an increase. Making the changes gradual and addressing them as soon as changes are noticed are the very best way to go about ensuring your fish will remain as happy and healthy as possible.