Turtles certainly do eat goldfish, and pretty much any other slow-moving fish that is small enough to fit in their mouths. They are omnivores, which means their diet mainly consists of plants, insects, snails, and of course, fish.
If you are planning on feeding your turtle fish, then goldfish are not advised to be used as a feeder fish for your pet turtle due to their spiny bones. They can cause damage to your pet turtle's throat and insides. Additionally, goldfish have a high-fat content, which isn't ideal for your turtle either.
If your turtle is being fed fatty foods constantly, they are much more susceptible to Vitamin E deficiency, which can lead to many health complications, such as an eye infection, weakened bones and shell, and slow healing. So, if you're looking for a feeder fish for your turtle, you will need to look for another type of fish species, rather than goldfish.
Can Turtles Live With Goldfish?
Turtles and goldfish are definitely not good tank mates, despite some lucky hobbyists having success with housing them both together. The problem is that goldfish are considered easy food by turtles as well as there being territorial disputes that come up along with a plethora of waste produced by both species.
A lot of the time, turtles will scratch and nip at goldies, and even eat the slower goldfish if they are small enough to fit in their mouth. However, in some other circumstances, turtles have been documented as totally ignoring the goldfish they live with, and they will typically not bother or try to eat larger goldfish.
Most of the time, the compatibility of both of these species is down to the tank size and also the turtle breed, but you would still be better off keeping your pet turtle with other fish species.
What Turtle Species Can Live With Goldfish?
There are many different aquatic turtle species, all possessing different characteristics and behavioral patterns, which makes some certainly more aggressive than others.
Red-Eared Sliders, Northern Red-Bellied turtles, and Peninsula Cooters are all compatible with Goldfish in both tanks and ponds.
Turtles that are not compatible with goldfish and should never be housed with them are snapping turtles, soft-shelled turtles, and musk turtles. All three of these turtles have a reputation for their biting and aggressiveness.
Something that has been theorized by many hobbyists is that if you add a turtle to a pre-established goldfish tank, they are far less likely to eat them or attack them.
What Goldfish Species Can Live With Turtles?
Funnily enough, goldfish species such as Shubunkins, Comets, Orandas, and Wakin goldfish are all between 10 to 15 inches (25 to 38cm) in size when they are fully grown, which is larger than a lot of aquatic turtle species. So, if you own any of these goldfish, expect your turtle to be on the receiving end of some torment.
Small to medium-sized goldfish species such as the twisty tail goldfish, butterfly goldfish, and ryukin goldfish all have a pretty decent chance of survival if the tank is large enough.
The problem is that goldfish and turtles are generally not a good match, and most of the time your turtle will only see your goldfish as food, and nothing else.
Why Should Goldfish And Turtles Not Live Together?
There are a good few reasons why both goldfish and turtles should not live together. They are at completely different levels of the food chain, they have differing water parameter requirements, and both turtles and goldfish produce an unholy amount of waste.
Both maintenance and monitoring are going to have to be used in excess to keep both species happy and healthy, and it comes with a lot of work for the owner.
1. Waste Production
Goldfish produce so much waste it requires owners to clean their tank more regularly than most freshwater fish combined. Goldies dispose of their waste at a frightening rate, which leads to a buildup of ammonia in the water.
Now, if you consider that turtles are virtually the exact same in terms of their waste disposal, but they are typically bigger, you will be left with an incredibly dirty tank in short order.
Purchasing a strong filter is certainly necessary, particularly if you own a turtle and maybe other fish, or if you just have a tank full of goldfish, but imagine if you have both species housed together in the same tank!
The issue with a dirty fish tank is that harmful bacteria will start to spread and can be extremely harmful to your tank community, causing diseases that can result in death very quickly.
2. Different Water Parameters
Goldfish most certainly thrive in cool water temperatures, anything that is higher than 74°F (23°C) is considered to be warm for goldfish. Now, on the flip side, most turtles need a much broader water temperature of 72 - 86°F (22 - 29°C).
Both prefer alkaline water, but the differences in temperature make housing them extremely difficult in the first place. Unsuitable water parameters for fish and turtles will only lead to health problems and a shorter life, unfortunately.
3. High Maintenance
Turtles and goldfish both require large tanks, a ton of attention, produce an abundance of waste, and can become aggressive when it comes to territory. So, you will not only need a bigger tank to house them all together, but you will also need to provide an abundance of hiding spots for your goldfish, a larger filtration system due to their waste, and much more.
Here are some answers to frequently asked questions posed by other hobbyists that are related to this topic!
What Fish Do Turtles Eat?
In their natural habitat, turtles will eat an abundance of different fish, and even sometimes jellyfish. Usually, turtles in captivity will be fed feeder fish by their owners, which provides more of a challenge for the turtle.
Some of these feeder fish include guppies, platies, bluegills, mosquitofish, tetras, killifish, and zebrafish. Feeder fish should always be used as a "special treat" for your turtles though - no more feeds than just a couple of times a month.
Neon tetras are a good choice as they are small and agile and able to evade your hungry turtle for longer than most making them work a little for their food.
Can Feeder Fish Kill A Turtle?
Feeder fish most certainly can kill turtles. They have spiny bones that can get lodged or just simply cause injuries to turtles' throats and intestines.
Additionally, some feeder fish may be carrying parasites and bacteria that will pass through to the turtle, making it ill and causing health problems that can easily result in death.