Caring for Goldfish in a Planted Aquarium

The aquarium hobby as we know it today wouldn’t exist had it not been for the Goldfish. It is one of the most popular and readily available pet fish. From personal experience, I know that it is a fish that is available even in some of the most remote parts of the world. While Goldfish are very popular, it’s a fish that is often pigeonholed into beginner fish or pond fish. While both represent the truth, it isn’t the complete truth. Goldfish are highly adaptable and can be compatible with many different types of aquariums, including planted tanks. You read that right. Goldfish can be kept in planted tanks. Caring for Goldfish in planted tanks is not very difficult. While Goldfish are quite common in the hobby and the planted tanks to a lesser extent, the combination of the two is rare, and that can help your aquarium stand out from the crowd.

Is that something that interests you? Follow along as we explore the wonderful possibilities presented by the combination of Goldfish and planted tanks.

Where To Start?

Generally, planted tanks are built around the plants. The fish are chosen based on how compatible they are with the plants. That strategy won’t work here as the Goldfish have certain requirements that would kill or stunt the growth of many aquarium plants. Others might fall prey to the huge appetite of these fish. The best strategy is to understand the care requirements of goldfish and then choose the plants accordingly.

Tempering Expectations

When thinking of planted tanks, most hobbyists will picture something that is lush and full of greenery with a fine substrate and plants of different sizes filling up the tank. The typical planted tank won’t work with goldfish in the tank as these fish love to dig around, move the substrate around, and, most importantly, they love to eat plants. A planted tank can take weeks or even months to get properly established, and goldfish can undo all that in a matter of hours.

You need to get creative with the plants you choose, and that will introduce a few compromises. The finished tank may not look like a standard planted tank, but it will still look splendid.

A Brief History Of Goldfish

Goldfish are a completely artificially created fish. They aren’t considered a species by the scientific community. The exact origin of this fish is unknown, but it is generally agreed that Goldfish have been in existence for at least a thousand years. They were selectively bred from the different varieties of Asian Carp in different parts of China. While these Carps are mostly silver-grey, they would occasionally produce fish that were more red, yellow, or orange. These were then selectively bred to create the goldfish. These are known as common goldfish nowadays. Modern breeders have taken things to an entirely new level. It is common to find many varieties often grouped together as fancy goldfish. These can be great choices for a planted tank, as we shall soon find out.

Basic Goldfish Care Requirements

Combining goldfish and plants requires a good understanding of what is needed to keep goldfish successfully. Let us start with the tank size.

Tank Size

The first thing that I want to get out of the way is that Goldfish, or any fish for that matter, should never be kept in a fishbowl. Many places will sell planted bowls with a goldfish or two in them. This is the worst possible way to keep goldfish. These fish require a proper tank. Plants also require a decently-sized tank to flourish. A 30-gallon tank is a bare minimum. Even then, you can only keep one goldfish which I do not recommend as these are social fish. Every additional goldfish will require between 12-15 gallons of water. A 60-gallon tank is what I prefer as a starting point, as that will allow you to keep a pair of these fish. It will also give you enough space to build a planted tank. The larger the tank, the better it will be in terms of maintenance as well.

Filtration

Goldfish produce copious amounts of waste, and this changes the water parameters quickly to unsafe levels if left unchecked. Normally, the solution is straightforward – install a powerful filter with a high flow rate. However, since we also need to keep plants, any powerful filter won’t do. A hang-on-the-back filter with at least two times the flow rate of the aquarium (if you have a tank that is 60 gallons, then the flow rate should be 120 gallons/hour) is the ideal option. These filters won’t create a current that is so strong as to hinder the growth of the plants while still being efficient enough to properly filter the tank.

Substrate

The substrate is where things get a bit tricky. As mentioned earlier, these fish produce a lot of waste. You need easy access to the substrate to clean the detritus out every now and then. While the plants will use some of the waste produced by the fish as nutrients, they won’t be able to deal with all of it. So, something like regular aquarium soil with fine particles won’t work. On the other hand, large gravel is great when it comes to maintenance, but it won’t work well for most plants.

Quartz gravel or any other gravel with a particle size of about 3mm is the perfect compromise for a planted goldfish tank.

Another option is to go for a bare-bottom tank. This will seriously limit the plant options to those that are already rooted to bogwood or other pieces of aquarium décor.

Goldfish Varieties That Are Best For Planted Tanks

The common goldfish is the most readily available and affordable goldfish. However, it also has the highest chance of destroying plants. Fancy varieties like the Celestial Eye, Telescope, Ranchu, etc., tend to be less inclined towards eating the plants. While this may not always work as a lot depends on the individual personality of the fish, fancier goldfish offer a higher probability of survival for the plants.

Plants That Are Best For Goldfish

Choosing the right goldfish for a planted tank may not be an exact science, but choosing plants for a goldfish tank is much more straightforward. The first requirement is that they should be fine with a lower water temperature. Unlike most tropical aquarium fish, goldfish are cold-water fish. The ideal water temperature for them is between 20°C – 23°C or 68 °F – 74°F.

On top of that, the plants need to be one of the following

• Inedible: Goldfish will go after the plants sooner than later. If they don’t like the taste of the plant, they will mostly leave it alone
• Tough: If goldfish have to put in a lot of effort to bite into the plant, then they won’t see it as a viable food option
• Fast-growing and cheap: These are the plants that can be used as sacrificial plants. These plants are edible, but they can regenerate quickly enough that they won’t get destroyed completely. They will keep the goldfish busy and away from other plants that may not grow as quickly

Finding plants that fulfill all these criteria is a bit difficult but not impossible. I have had great success with the following plants in my goldfish tank.

• Amazon Sword: These are some of the toughest aquarium plants that are also readily available and cheap. They look good and can be planted in a number of ways. They can take root in larger gravel substrates as well. Goldfish will occasionally take a nibble at them, but in most cases, the Amazon Sword will be left unscathed. The only caveat with these plants is that they prefer slightly warmer water than is ideal for goldfish. The trick that has worked for me is to keep the temperature at about 25°C or 77°F when planting them. Once they root themselves and start growing new leaves, I lower the temperature to the ideal range of the goldfish.
• Pond Weed: This option falls under the category of sacrificial plants. Goldfish love to munch on them. This is offset by the plant’s ability to grow quickly. Even if the goldfish end up eating them completely, they can be replaced easily as they are quite cheap, even though I have never had a bunch of pond weed disappearing on me completely. 
• Moss Balls: This one falls under the category of inedible. Most fish, including goldfish, tend to hate the way moss balls taste. After an exploratory bite, goldfish will most likely leave these plants alone. An added advantage of these plants is that they do not require any substrate, and they can act as great toys for the fish.
• Hornwort: This is another fast-growing plant that can keep up with the near insatiable appetite of these fish. It does not need to root. You can leave them floating or weigh them down to strategic points inside the aquarium to create a good-looking setup.
• Ludwigia: All planted tanks need a centerpiece plant that acts as the focal point for the plants, and the Ludwigia is a great centerpiece plant for goldfish tanks. They come in different colors that make them stand out instantly. The way they spiral out fills the tank in a very satisfying manner. They are pretty tough too. The catch here is that these plants require a stronger level of lighting as compared to the other options listed here.
• Java Fern: Goldfish generally do not find these plants palatable and will mostly leave them alone. They may keep tugging at them, but the Java Fern is resilient enough to withstand that as well. The biggest advantage of keeping these plants is that they can be rooted to almost anything, including driftwood, bogwood, pebbles, rocks, and aquarium décor. This is perfect if you are going the hardscape route (more on that later).

Cryptocorynes: If you plan on keeping a tank that is north of 120 gallons, then this a great plant. It grows tall and is very tough. It also lives for a reasonably long time and can last for years. The only downside with these plants is that they aren’t readily available, and good specimens can be quite costly.

Your Mileage May Vary

It is worth remembering that these plants offer a best-case scenario when kept with goldfish. They aren’t totally resilient to goldfish. I have had certain fish that would just destroy plants for the heck of it. They would see a tough or inedible plant as a challenge and keep attacking it until it is ripped to shreds. The entire process of setting up a harmonious planted goldfish tank may take a few tries. Either keep a separate tank where you can move particularly notorious goldfish to or look for a pet store that will take such goldfish and exchange them for different ones. Eventually, you will end up with a group of goldfish that will have a relatively passive mindset toward plants.

Lighting For Planted Goldfish Aquariums

Almost all the plants that are tough enough to be kept with goldfish will have modest lighting requirements. Standard LED aquarium lights that output about 0.25 watt per liter or about 1 watt per gallon is good enough. Exceptions include plants like Ludwigia, which require about double the wattage. 

A balance must be found as lights that are too powerful will wash out the fish’s colors and lead to an algae bloom, while lights that aren’t powerful enough will lead to improper growth in plants.

Is Hardscape A Good Option For Goldfish?

Hardscaping is the type of aqua scaping where things like stones, rocks, driftwood, etc., are used to create the tank layout. You can use hardscaping as the base for the planted goldfish tank. Add hardscape elements such as rocks and branches with plants like Java Fern already rooted in them to create a very sparse yet distinguished look. This style of aquarium, while being classy, is also very resilient to goldfish.

How To Stop Goldfish From Eating Plants

There are no hard and fast rules that will give you instant success, but these strategies will improve your chances immensely

• Start with the plants: As mentioned before, most plants require slightly warmer water than is ideal for goldfish. Allowing the fish to get established at its ideal temperature and then bringing the temperature down gives it the best chance of surviving. It also gives the plants enough time to acclimatize without being under constant attack from the goldfish
• Add smaller goldfish: The goldfish’s affinity towards plants will increase with size. Starting out with smaller fish will reduce the damage inflicted on the plants. By the time the fish will grow large enough to inflict serious damage, the plants would have toughened up as well.
• Be ready to experiment: A planted goldfish tank is like the moving staircases in Hogwarts. Things will keep changing and evolving. There will be minor setbacks. Don’t get disheartened and abandon the idea of a planted goldfish tank. Instead, stick to it, and you will end up with something that you can be proud of while also getting to learn a lot of new things about the hobby.
• Keep the goldfish well-fed: Most goldfish will relentlessly try to eat aquarium plants only when they are hungry. If they have access to a food source that doesn’t require as much effort, then they will mostly choose that option.

Setting Up The Goldfish Planted Tank

Here are the steps involved in setting up a planted goldfish tank

1. Place the tank on a sturdy surface strong enough to bear the weight of the tank when it is full
2. Clean the tank with regular water and ensure that there are no leaks
3. Add the substrate/hardscape
4. You can do the planting before or after filling up with water. I have had almost equal success with both
5. Install the filter and turn it on
6. Cycle the tank and keep testing for ammonia, nitrites, and nitrates.
7. Once the tank is cycled, it is technically ready to take in the fish, but I would recommend waiting for just a touch longer to allow the plants to establish themselves
8. After all the plants show new growth in the form of leaves, stems, and/or roots, the tank is finally ready to accept the goldfish

Monitor and test the tank continuously for a few days. If any fish are relentlessly aggressive towards the plants, then have them replaced

Water Parameters

The ideal water parameters for goldfish are as follows

Feeding Goldfish In A Planted Tank

There are no restrictions to feeding a goldfish because of the plants. However, you can use it to improve the chances of the plants’ survivability. Feed the goldfish 3-4 times a day. Normally, it is advised to keep these fishes slightly underfed to reduce the waste they produce. However, that strategy won’t work here. Keeping them properly fed will make the plants seem a lot more unappetizing.

As for the food itself, a high-quality fish food specially formulated for goldfish is your best bet. Both flakes and pellets work well. Supplement that with live or frozen brine shrimp, duckweed, and scalded peas.

Maintenance Of The Goldfish Planted Tank

While most planted tanks require less frequent water changes, goldfish require frequent water changes even in a planted tank. I have found the most success with a weekly water change of about 25%. Monitoring the nitrates is the best strategy, though. Do a water change as soon as the nitrate level starts approaching 50 ppm.

Goldfish Diseases In A Planted Tank

There are no specific diseases that affect goldfish because they are in a planted tank. However, they do have a long list of diseases that can afflict them. Some common ones include

• White spot disease
• Anchor worms
• Fish lice
• Hole in the head disease
• Polycystic Kidney Disease

Usually, as long as the tank is maintained properly and they are fed well, goldfish will remain healthy. Quarantining new fish goes a long way in ensuring that no new pathogens are introduced. Some of the fancier goldfish will develop issues like digestive problems, buoyancy disorders, blindness, etc., with age. There is very little that can be done in such cases, and it is best to avoid fish with extreme physical deformations in the first place.

To Sum Things Up!

I will never say that keeping goldfish in a planted tank is easy but what I can say with confidence is that you will have a whale of a time. It does take patience, effort, and being okay with temporary setbacks. The key is to choose the right plants. Get them established and accustomed to the lower temperatures preferred by goldfish. Choosing the right goldfish through trial and error and by monitoring closely for the first few weeks.

Setting up a planted goldfish tank is slightly more challenging than either a regular goldfish tank or a planted tank, but considering how spectacular the end result is, it is well worth the extra trouble.

FAQs

How Long Do Goldfish Live?

The typical goldfish lifespan is between 10 and 15 years. Fancier varieties tend to have a shorter lifespan.

Where To Buy Goldfish Near Me?

Almost all pet stores, both large and small, will have goldfish. These days, you can even order them online. Going to a shop and choosing healthy fish is recommended, though.

Can You Eat Goldfish?

It comes down more to personal taste. Goldfish are edible, but they don’t offer any benefits in terms of nutrients or taste. If anything, they have a higher fat percentage

What Do Goldfish Eat?

Goldfish are voracious omnivores and will eat pretty much anything they can fit in their mouths. For their good health, it is best to provide them with good quality fish food formulated specifically for them. This can be supplemented with live or frozen food.

How Big Can Goldfish Get?

Goldfish, like all fish, keep growing throughout their life and since these fish can live for 10-15 years, they can grow to be quite big. Their maximum size also depends upon the size of the tank. If they have access to a lot of space, goldfish can grow to a maximum size of 14 inches or 36cm.

Where Do Goldfish Live?

Goldfish aren’t a naturally occurring fish and cannot be found in the wild

How To Tell Sex Of Goldfish?

Females tend to be rounder and deeper-bodied, while males tend to be longer and more slender. During the breeding season, males will develop small white spots on their gills while the females will become gravid with eggs which can be identified by their bellies protruding more on one side

Where Do Goldfish Come From?

These are captive-bred fish that are believed to have been first bred in China

Do Goldfish Get Lonely?

Goldfish are social fish and do best when kept in groups of at least two.

How Long Is A Goldfish’s Memory?

There is a popular misconception that goldfish have a 3-second memory span. This is not true, and studies have shown that goldfish have an impressive memory, and they can even learn to recognize their owners

Do Goldfish Need A Heater?

Unless the temperature drops below 10°C or 50°F, goldfish do not need a heater

Can you put live plants in with goldfish?

You most certainly can. Great options include Amazon Sword, Moss Balls, Java Fern, Ludwigia, etc.

Can you Aquascape with goldfish?

Yes, you can

Can live plants harm fish?

No plant meant for aquariums can harm fish unless the fish get entangled in them or choke on them

Do goldfish need fake plants?

They don’t mind fake plants, and this is the much easier option to get the planted goldfish aquarium look

Do goldfish like still or moving water?

They prefer the presence of a water current in the tank but it should not be too strong

Will plants break down fish poop?

They will to a certain extent, but you will still need to install a proper filter and do water changes on a regular basis