Goldfish Care Sheet

by Kevin Tan

his is a simple beginners guide to owning a first goldfish tank.

The Objective: To get three small goldfish and see them thrive and mature, living a normal full life span of 5 to 10 (or more!) years. These instructions will introduce the basics; use it as a starting point.

Step 1: Basic Needs - Things to Buy


Goldfish need quite a bit of space for a few reasons. They are relatively fast growers. They are messy. They are voracious, but at the same time they require high quality water to thrive. Be aware that small goldfish can potentially grow up to 10-15cm within a year! Buy the biggest tank you can afford or you will be looking to upgrade pretty soon.


Because of their voracious and messy nature, goldfish require large filters. We recommend getting external canister filters for better filtration. The flow controls on these filters are also good and appropriate; goldfish don't like to swim against a big current all the time. We recommend the Aqua-One range of Canister Filters as we feel they are good value for money. Internal powerfilters are not recommended for goldfish tanks as these do not provide enough surface area on their media to cope with the waste load of goldfish and create too much of a current in the tank.
Good Filtration is Essential!

Water Conditioners

Water conditioners are necessities when keeping fish in Australia. The municipal water contains chlorine and chloramines and if not removed from the tap water will kill fish.

We recommend Sera Aqutan which is a 5-in-1 conditioner for your aquarium water.

Other Important Stuff

A gravel vacuum for cleaning the tank and changing water. Two buckets that you can comfortably lift full of water; one for removing old water and one for aging fresh water. An algae scrubber for the tank glass. An in-tank thermometer or Digital thermometer .

Optional Stuff

Gravel: A goldfish tank with no gravel is easier to keep clean. If you do put in gravel, make it only a thin layer say 3cm deep. Both you and the goldfish will find this easier to clean.

Plants: the fish will eat some live plants, but that's only bad for the plants. Ask us what plants do well in Goldfish tanks. We have an extensive range of plants grafted on rocks and wood that are hardy and tough and are great in goldfish tanks.

Light: Would certainly help with the colour and vibrancy of the fish ... definitely a must if you want to have plants.

Heater: Heaters are optional in a Goldfish tank. Some of the more fancy varieties do benefit from keeping the water temperature no less than 20degrees C.

Step 2: Setup


The tank must be on a strong level surface that can support the weight. Remember, water is HEAVY! A standard 2ft aquarium with water and ornaments in it can easily weigh 70-80kg!! Do not put the tank where it will receive direct sunlight. Try to put the tank in a spot where the temperature is fairly steady during the day.

Remember, this is an aquarium and you will inevitably spill water around the tank.... NEVER put the tank on an appliance, antique, etc.


Fill the tank with water. Always de-chlorinate tap water before use.

Step 3: Cycling the Tank

This is really important. Fish produce ammonia as a waste product (goldfish produce a lot of ammonia!). It's very toxic. There are two kinds of good bacteria, one that turns ammonia into nitrite (also toxic!) and another that turns nitrite into nitrate (relatively harmless). You need to give the tank time to develop these good bacteria on the surfaces of the tank and filter.

We suggest using a bio-starter such as Sera Nitrivec to kick start your cycling process.

Step 4: Selecting Fish


Select healthy, active fish. If there are any sick fish in the tank, avoid buying from the tank. Never buy fish that float at the surface whenever they stop swimming. At Slippery Little Suckers, we constantly monitor the health of our goldfish.


There are hundreds of varieties of goldfish. Pick what you find attractive. There are Orandas, Lion heads, Ranchus, Ryukin, Telescope eye demikin, Pearlscale and many many more.

Step 5: General Care


Feed the goldfish as much as they can finish in two minutes, twice a day. Feeding sinking food is advisable with many of the short-bodied fancy varieties. Supplement their diet with frozen bloodworms and peas that have been popped out of their skins and blanched leaf greens. This will help alleviate any swim-bladder problems the fish may develop.


Use the gravel vacuum to clean the poop out of the gravel once a week to once a fortnight. If you have algae, clean it off the front glass but you may choose to leave it elsewhere (the fish will nibble on it). Change a maximum of thirty percent of the water once a week to once a fortnight. Finally, clean out the filter element every couple of weeks, rinsing it in used tank water (tap water could kill the good bacteria!).


Not very critical. A water temperature of 24degrees Celsius is considered ideal. Above 32 degrees Celsius, some fish may suffer and even die.

Step 6: Becoming a Hobbyist

If you find you enjoy your fish, consider consorting with others that feel the same! Participate in internet discussion groups, subscribe to aquarium periodicals, ... learning about goldfish and meeting new people can be an additional level of fun above and beyond keeping our finny little friends.

Note: Tank capacity for goldfish

Many people react very skeptically to the large tank volumes recommended for goldfish. The short answer is that goldfish are different from tropical fish. Their keepers also are different. When you obtain a goldfish as a pet, you are obtaining a responsive and intelligent (for a fish, anyway) creature that you can expect will live as long as a dog or cat would. Based on this, the goldfish keeper is a collector of individual fish rather than a collector of indistinguishable schools of interchangeable specimens.

Never think that you need to buy a dozen fish because half will die in the first week. This is a self-fulfilling prophecy. With this in mind, take the time to select one or two goldfish that hold special attraction for you when you start out. Then give them the care they deserve to thrive. You will quickly find that a tank with a pair of special fish with character in it doesn't seem empty at all.

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