Goldfish Tank Size
Tank size is one of the most important factors in Goldfish care. This is one of the key elements that will differentiate between surviving and thriving!
Water quality is the number one reason Goldfish get sick, so ensuring your tank is adequately sized means the water quality is much easier to maintain. Allowing your fish to live the loves they deserve - happy and healthy.
Goldfish grow very big, very quickly. During their first three years, they will quickly become the size of your hand... and beyond! They also love to swim. Even the fancies with their big deep bodies need lots of space to move around to enjoy their lives. Single tailed Goldfish are very fast, and require long tabks with good turning space in order to thrive.
It's not just their size though, they produce tonnes of waste too. They are omnivores, which means they take in a lot of plant/vegetable matter. This means they poop like crazy as they pass the plant matter through their systems.
Poop isn't the only waste they produce. Most of the ammonia they produce is excreted through their gills, so you won't even see the tank filling with toxins, like you see the tank filling with poop! They also produce hormones and if these are left to build up, they can cause stunting and other serious health issues.
These are just a few of the reasons Goldfish require large tanks. The more water we have, the more diluted waste product becomes. Okay, a cycled tank wouldn't have any ammonia but ammonia is converted to the end product, Nitrates, during the cycle. More ammonia = more nitrates.
Water quality is the number one reason Goldfish get sick, so ensuring your tank is adequately sized means the water quality is much easier to maintain. Allowing your fish to live the loves they deserve - happy and healthy.
Goldfish grow very big, very quickly. During their first three years, they will quickly become the size of your hand... and beyond! They also love to swim. Even the fancies with their big deep bodies need lots of space to move around to enjoy their lives. Single tailed Goldfish are very fast, and require long tabks with good turning space in order to thrive.
It's not just their size though, they produce tonnes of waste too. They are omnivores, which means they take in a lot of plant/vegetable matter. This means they poop like crazy as they pass the plant matter through their systems.
Poop isn't the only waste they produce. Most of the ammonia they produce is excreted through their gills, so you won't even see the tank filling with toxins, like you see the tank filling with poop! They also produce hormones and if these are left to build up, they can cause stunting and other serious health issues.
These are just a few of the reasons Goldfish require large tanks. The more water we have, the more diluted waste product becomes. Okay, a cycled tank wouldn't have any ammonia but ammonia is converted to the end product, Nitrates, during the cycle. More ammonia = more nitrates.
Tank Volume
Fancy Goldfish require a bare minimum 80L/20G for the first fish and 60L/15G for each Fancy thereafter. Single Tailed Goldfish require 120L/30G per Single Tailed Goldfish.
These are minimum guidelines and you should be prepared to upgrade as they grow.
A better guideline to follow for Fancy Goldfish is 80L/20G per fish. This allows much more swim and grow room for them, as well as allowing extra water volume to dilute waste.
Bigger is always better (Sorry lads, it's true!), I would always recommend that you side on understocking your tank. The less fish in the tank, the less waste that will be produced. There is nothing better for fish than pristine water, the fewer fish you have, the easier this will be to maintain.
These are minimum guidelines and you should be prepared to upgrade as they grow.
A better guideline to follow for Fancy Goldfish is 80L/20G per fish. This allows much more swim and grow room for them, as well as allowing extra water volume to dilute waste.
Bigger is always better (Sorry lads, it's true!), I would always recommend that you side on understocking your tank. The less fish in the tank, the less waste that will be produced. There is nothing better for fish than pristine water, the fewer fish you have, the easier this will be to maintain.
Tank Dimensions
Goldfish, particularly Fancies, tend to struggle in deep water. Their Swim Bladder and deep body shape mean that some will find it hard to swim happily in deep tanks. Long, shallow tanks are much better for them.
I would aim for something no deeper than 24", anything deeper has the potential to either cause issues, or not help them, at the very least.
One of the treatments used for Swim Bladder Disorder and long term care is shallow water, so I always think it's best to ensure the water is shallow before we have an issue we need to fix. Prevention is always better than cure!
Personally, looking at my chubbies, I wouldn't keep Fancies in anything less than 36-48" and Single Tails would require something closer to 60-72" in order to be able to swim comfortably. Single Tailed Goldfish can easily reach 12-15" in body, so a 24" 30G tank would not be a suitable home for a fully grown Single Tailed Goldfish.
Of course, there is such a thing as too shallow. We want our guys to be comfortable, so ensure your fish could stand in its tail end and still have it's nose in the water as a good minimum guideline.
The wider the tank, the better. My guys suck at turning. It's like watching my mum try and do a three - point turn on a narrow road - it takes forever (and a lot more than three points.... sorry Mum!!). Granted, my guys are big but I get the impression that the bigger they get, the harder it is for them to turn smoothly; upside down, back to front, on your side is the usual method for some of my monsters! Aim for something 15" or wider (especially if you have Single Tailed Goldfish, you're probably aiming for something closer to 24") to ensure they can comfortably manoeuvre around the tank.
I would aim for something no deeper than 24", anything deeper has the potential to either cause issues, or not help them, at the very least.
One of the treatments used for Swim Bladder Disorder and long term care is shallow water, so I always think it's best to ensure the water is shallow before we have an issue we need to fix. Prevention is always better than cure!
Personally, looking at my chubbies, I wouldn't keep Fancies in anything less than 36-48" and Single Tails would require something closer to 60-72" in order to be able to swim comfortably. Single Tailed Goldfish can easily reach 12-15" in body, so a 24" 30G tank would not be a suitable home for a fully grown Single Tailed Goldfish.
Of course, there is such a thing as too shallow. We want our guys to be comfortable, so ensure your fish could stand in its tail end and still have it's nose in the water as a good minimum guideline.
The wider the tank, the better. My guys suck at turning. It's like watching my mum try and do a three - point turn on a narrow road - it takes forever (and a lot more than three points.... sorry Mum!!). Granted, my guys are big but I get the impression that the bigger they get, the harder it is for them to turn smoothly; upside down, back to front, on your side is the usual method for some of my monsters! Aim for something 15" or wider (especially if you have Single Tailed Goldfish, you're probably aiming for something closer to 24") to ensure they can comfortably manoeuvre around the tank.
Tank decor
One important thing to remember when stocking/decorating your tank is that anything that goes into the tank takes up space. Space means volume. The more "stuff" in your tank, the less volume of water the tank holds.
That includes everything; substrate, heaters, wood, stones, filters, caves, plants.... everything you add removes water volume.
Internal filters can be very bulky and take up lots of room. Whilst filtration is necessary, we don't want to lose volume or swim space within the tank, so Hang on the Back (HOB), canisters and sumps are better options, in terms of filtration as they stay outside the tank.
Keep substrate to a minimum, a fine layer of sand is all that is needed.
Consider large rocks and wood when you are stocking your tank - how big are they? Can you afford to lose that much volume? If you're even slightly overstocked, large wood and rocks can make matters much worse as they remove a surprising amount of volume from the tank!
Plants are a little different, they don't remove the volumes of water that large, solid decor does and also aid you in keeping water quality good. Ensure your fish have ample swimming room and consider this when decorating, but you can go a little bit wilder with plants than you may with solid decor.
This allows maximum usage of the tank space.
That includes everything; substrate, heaters, wood, stones, filters, caves, plants.... everything you add removes water volume.
Internal filters can be very bulky and take up lots of room. Whilst filtration is necessary, we don't want to lose volume or swim space within the tank, so Hang on the Back (HOB), canisters and sumps are better options, in terms of filtration as they stay outside the tank.
Keep substrate to a minimum, a fine layer of sand is all that is needed.
Consider large rocks and wood when you are stocking your tank - how big are they? Can you afford to lose that much volume? If you're even slightly overstocked, large wood and rocks can make matters much worse as they remove a surprising amount of volume from the tank!
Plants are a little different, they don't remove the volumes of water that large, solid decor does and also aid you in keeping water quality good. Ensure your fish have ample swimming room and consider this when decorating, but you can go a little bit wilder with plants than you may with solid decor.
This allows maximum usage of the tank space.