A thermometer is an essential addition to any aquarium. Maintaining the right temperature is key to
the health of your fish. But reading the thermometer can confuse a lot of people. Here are some of
the easy steps to follow to control the temperature in your aquarium.
Finding the Right Temperature
Let’s start by figuring out what temperature you should be maintaining your thermometer at. This
will often depend on the species that you are housing. In most cases, this will mean keeping the
water between 25 to 27 degrees Celsius (76 to 80 degrees Fahrenheit).
If you are in doubt about what temperatures your fish will prefer you can search online.
Alternatively, you can ask a pet store or consult with your vet. If you have multiple fish you should
aim for a temperature that will be best for the group as a whole. This article goes into more depth
about the ideal temperature and why getting the right setting is so important.
Tips on Choosing an Aquarium Thermometer
The next thing that you need to do is find the right thermometer for your fish tank. There are a few
options that you can use. Some people prefer stick-on thermometers. These go on the outside of the
aquarium and come with an LCD display. It will use a color-coded system to give you an estimate of
the temperature of the water. This is popular because it lets owners know at a glance whether they
need to take action.
Alternatively, you can use a digital display. These feature a sensor that goes into the tank. The
thermometer will sit on top of the tank. Often, the sensor will use a wire, though you can spend a
little more and get a wireless option. At other times, these digital thermometers will sit inside the
tank and will be attached using a suction cup.
Regardless of which option you want to purchase, there are some things that you need to consider.
First, need to think about how much it will cost. You shouldn’t have to spend a fortune to get a
thermometer. You should also consider how accurate it will be. The best way to do this is by looking
at the reviews. This aquarium thermometer guide will help you narrow down the right option for
Installing the Thermometer
In most cases, it will be fairly easy to install the thermometer. If you are using a digital thermometer,
either put the thermometer in the tank or install the sensor. It should start working instantly. Then,
all you need to do is remember to do is change the batteries.
If you are using a stick-on thermometer, you need to clean the area with a damp cloth to get rid of
any dust. Then, remove the sticky strip. Make sure that it is on straight. You can use your credit card
to remove any air bubbles that are forming on the thermometer. It will take 30 minutes before it
starts working. This article talks you through these steps.
Reading the Thermometer
Once you have got everything set up, it will be time to start using the thermometer to monitor the
temperature in the tank. How you do this will depend on the type of thermometer you got. A glass
and digital display will be fairly self-explanatory. It will display a number, which is the temperature
inside the tank.
However, a stick-on thermometer won’t be as easy to understand. In most cases, there will be three
colors; blue, green, and red. Each will display a different number. This tells you the range of
temperatures that could be in the tank. The blue numbers tell you the bottom of this range, with red
representing the top. The green will be the most likely temperature inside the tank. Sometimes, it
can be a bit tricky to see these figures. It can help to use a flashlight.
It should be noted that stick-on thermometers might be affected by the outside air temperature. To
minimize this risk, you will need to be careful about where you are putting the thermometers. For
example, you don’t want to put them under a heater or air conditioning unit.
Other Signs of Unpleasant Water Temperatures
While an aquatic thermometer is one of the best ways to tell if something is wrong, there are a few
other signs that you can look for. First, will be unusual behaviors from the fish. If they are stressed by
the heat, they will start to use their gills more rapidly. This could be a sign that they are gasping for
You should also look at the conditions of the tank. Sometimes, you will be able to see algae building
up. This is often a sign that it will be too hot in the water. This could be why the base of the tank has
started to become cloudy.
On the other hand, if the tank has become too cold, the metabolism of the fish will slow. As a result,
they will appear sluggish. The low oxygen levels might also cause them to start gasping for air.
You’ll need to be attentive to these signs. If the fish continues in this stressed state for too long, it
can start to damage their health. In extreme cases, it can even lead to death.
What Affects Water Temperature?
There are a few things that will affect how hot or cold your water will become. The most common is
where you have positioned the tank. For example, it might be near a window. This means that the
heat from the sun can warm it up. This can produce sharp changes in the temperature of the water
throughout the day. Even with a good thermometer, it will be hard to control the temperature under
Another common problem is putting the tank near things like heat exhausts, ovens, or air
conditioning units. When in operation, these devices can have a big impact on the temperature of
The next factor to consider is how much water is in the tank. During a warm summer day, it’s
common for evaporation to lower the water levels. The lower they become, the more easily the
temperature of the tank will fluctuate.
Controlling the Temperature of the Tank
Once you know the temperature, you’ll be able to start working on controlling the temperature inside
the tank. There are a few simple ways that you can do this.
During the winter months, it will often be necessary for you to cool the tank. To do this, you will
need to install water heaters. There are a few things you will need to consider. First, you’ll need to
find the right size. This will often depend on how much water will be in your tank. Often, the larger
the tank, the less wattage your heater will need to be. This is because it will take longer to cool once
In general, a 20-gallon tank will need a 100-watt system, while a 100-gallon tank will need around
300-watts. You’ll also need to think about how many heaters you are using. For a smaller system,
you might only need one. This should be in the middle of the tank. However, if you have a larger
tank, you might want to use two. This will reduce the problems if one breaks down. These will need
to be on opposite ends of the tank.
You’ll also need to think about how you are going to cool the tank during the summer months. There
are a few ways to do this. First, you can increase evaporation. As the water evaporates, it will cool
the tank down. You can set up a fan to cause gentle ripples across the water surface. Or you can get
a device that will blow air bubbles. If you are taking this approach, though, you need to make sure
that you are topping up the lost water gradually.
If you have a severe summer, you might need to take more dramatic steps to cool the water. This
can include putting bottles of frozen ice into the water. Or you can use ice cubes. This can be a good
way of combating the water that you are losing to evaporation.
Finally, you might want to add a chiller to your tank. This will help keep water cold. This might only
be needed if you have species that are sensitive to temperature changes in the water. This is most
common in tropical species.
You must keep a close eye on the temperature in your fish tank. Too high or too low and the fish will
become stressed. This is bad for their health and might even lead to death. The good news is that a
thermometer tells you the temperature at a glance. This will make it easy to decide if you need to
make any adjustments. Hopefully, you now have a better idea of how to install and read these devices.