Can I Put a Turtle in My Fish Tank

The short answer is yes. You can put a turtle or turtles in your fish tank. However, there are a million and one things to consider. In other words, you need to take into account many things to have a thriving fish and turtle community aquarium. If you don’t you could end up with a disaster. For instance, the turtle you introduce could eat your fish friend overnight. 

Because there are so many things to take into account and so many risks, many experienced aquarists advise against adding a turtle or turtles into a fish tank.

Nevertheless, in this post, you will learn the things you need to consider to make a fish – turtle aquarium work. There are many things to consider and it is a lot of hard work to make a fish tank also suitable for a turtle. However, the end result is almost always worth it in my opinion because a fish – turtle community tank is often interesting to own and look at.

Key Things to Consider Before Putting a Turtle in Your Fish Tank

1. Space

Space is perhaps the most important thing you need to consider before putting a turtle in your fish tank. Turtles need space. They need plenty of space because they usually grow big. The minimum amount of space per turtle shell inch is 10 gallons. Therefore, considering the average size of pet turtles, you should not put a turtle in any tank below 55 gallons because the space in it will probably be too small.

Many experts recommend tanks of at least 75 gallons for one turtle. So if you want to add a turtle to your fish tank, make sure your tank is at least 75 gallons in volume. If it is not, buy one that is so that you can properly accommodate a turtle and your fish.

If you put a turtle in a tank that is too small, it will get into confrontations with the fish in it. And this could result in a disaster.

2. Filter

Before putting a turtle in your fish tank, you should ask yourself how powerful your filter system is. If you conclude it is not powerful enough, you should get yourself a powerful canister filter. Why do you need a powerful canister filter? Because turtles typically emit much more waste than fish.

So introducing a turtle will increase the amount of ammonia and other toxic chemicals that need to be constantly eliminated from your fish tank. If your filter is not powerful enough, the concentration of ammonia in your tank could increase to the extent of harming or killing your fish.

Therefore, before putting a turtle in your tank, you should consider getting and installing a decent canister filter.

3. Air Pump

If you do not have an air pump, you should not even think about adding a turtle into your aquarium. The reason why is that many aquatic pet turtles breathe underwater. Therefore, if you do not have an air pump, it means your tank will not have enough oxygen for both your fish and your turtle. This could result in low oxygen levels and even suffocation for both your fish and your turtle.

So if you really want to put a turtle in your fish tank, you should add an air pump if you do not have one. If you have an air pump, you should make confirm if it works well by getting an oxygen test kit. If it does not work well, you should get a better and more powerful pump to supply more oxygen to your fish and the turtle you want to introduce.

4. Hiding Places

This is one of the most important things to consider before adding a turtle to your fish tank. Many turtles in tanks usually get attracted to fish and end up chasing them every now and then to eat them.

Therefore, before putting a turtle in your tank, you should assume that it is going to want to chase your fish around and you should prepare for that possibility. The best way to prepare is to add hiding places such as commercial fish hideouts, rock caves, driftwood, PVC pipes, and glass bottles. 

Live plants do not qualify as hiding places for fish in this scenario because all pet turtles can easily swim through them.

So if you do not want your fish to end up getting eaten alive by the turtle you want to introduce, you should add hiding places. 

5. Turtle Species

Before putting a turtle into your tank, you should think about its compatibility with the fish you are keeping. If the turtle species you end up introducing is not compatible with your fish, it can harm, kill or eat your fish.

The worst turtle species to keep in a tank are cooters, painted turtles and red-eared sliders. This is because they like hunting and eating fish. If the species you want to introduce in your tank is one of these, you should wait until it is a bit older and mature. This is because when matured, these turtle species start preferring greens and veggies to fish protein.

Otherwise, if you are not yet decided, the best turtle species to buy and put in your aquarium is the Mississippi Map Turtle. This is because it seldom shows aggression and it is a good community tank. It rarely hunts or fights with fish. So if you have it together with compatible fish in a big tank with hiding places, there shouldn’t be any problems. 

6. Fish Species

Before introducing a turtle into your fish tank, you should check to see if your fish is compatible with it. A compatible fish species is that which obviously does not attack turtles. In other words, it is a species that is not aggressive.

A compatible fish species is also that which is fast enough to get away from a turtle that has gone berserk and wants to eat it. It is also one that is intelligent and acts fast to avoid getting into confrontations with turtles.

The best fish for keeping with a turtle in a fish tank are Zebrafish, Tetra fish, and Yellow Cichlids. Zebrafish and Tetras are particularly known to be intelligent, fast, and non-aggressive. They are the best fish to keep with a turtle. So if your tank does not have a fish, you should strongly consider one of these three species. If your tank already has a fish, you should consider replacing it with one of these three species.

The worst fish for turtles are those that are dangerous and can hunt, harm, maim, or kill turtles. They include electric eels, piranhas, and catfish.

7. Basking Space and Basking Light

If you really want to host a turtle in a fish tank, you should get a basking platform and a heater. This is because turtles are cold-blooded animals. Therefore, they occasionally need to come out of water and water up for a few minutes. Therefore, if your fish tank does not have a basking platform on which your turtle can relax and get warmed up, it will get cold in the water and die.

There are many turtle basking platforms available online. Simply find one that is suitable for your fish tank and buy it. Also, buy a basking light for your fish tank. There are special basking lights/ heaters for basking turtles available online. They heat basking turtles the right way to completely dry them up and warm them up.

So you need to install a basking platform and a basking light/ heater before you introduce a turtle into your fish tank. Otherwise, the turtle you introduce will die of cold.

Conclusion and Advice

As you can see from the information above, there are many considerations to take into account before putting a turtle into an aquarium. The considerations include space, filter, heater, basking space, fish species, turtles species, and so on. All the considerations are important for building a great ecosystem. 

If you think considering all the things above is too much work, then maybe you should not put an aquarium in your tank. As stated earlier, many experienced aquarists advise against putting a turtle in a fish tank because they know there are many risks. There is no other way to avoid the risks and create a great fish – turtle community tank than to take the considerations into account.

It may be a lot of hard work making changes to your fish tank to make it suitable for a turtle but it is totally worth it in my opinion. Because having fish and a turtle in a single tank makes it look super interesting and fascinating.