Caring For Goldfish 101 Exactly What You Need To Know

Caring for goldfish is a dream for many children… their first pet.

Back when I was a child I would beg my parents for my first pet. I mean we had a cat… but Fluff was the family cat…

I dreamt of having a pet that I could call my own.

After numerous weeks of begging my dad finally gave in and it was decided… I could get a goldfish.

I was over the moon, to say the least.

You see goldfish are so low maintenance that they make the perfect first pet. Just choose the best fish tank for goldfish, a filter, fill it up and you are good to go.

Going on holiday?

Not a problem, nowadays you can get an automatic feeder to take the strain off the neighbors.

Goldfish just don’t give a crap as long as they have food (Learn how many pellets to feed goldfish) and a clean tank!

Caring for goldfish is easy when you know how. Let me show you how to care for your new goldfish…

Say No To Fish Bowls

Fish bowls might look cool and fit the decor of your house. When it comes to caring for goldfish though they are just cruel…

Bowls are far too small especially at the top and this is the most important part. This is where oxygen will enter the tank. Having a small surface area for oxygen to enter means less oxygen for the goldies.

The first time I experienced this I thought they were coming to the surface for food or attention… Doh!

They were gasping for air!

I want you to think back to the last time you were at a funfair. Think of the funny mirrors that make you look all distorted. This is how a fish will perceive you through a fish bowl.

Pretty creepy, right?

Can you tell I am trying to sell you on the idea of a tank?

They come in a wide variety of sizes from very small… to very big. The glass is super clear too, no scary distorted humans coming towards your goldies.

The last thing is that they have a larger surface area for oxygen to enter. No more gasping for air goldies.

Check out my best fish tanks reviews. In this article, I share my best tips for choosing your next fish tank. I also share my 5 top recommendations!

Thinking of keeping Common Goldfish? Choose the best tank size for them…

Choose The Best Goldfish Tank Filter

Choose The Best Goldfish Tank FilterWhen I first got my first pet goldfish I was over the moon but having a water filter never crossed my mind. I just filled it up, decorated and then added the fish.

They must have been raging!

If you are unsure if your goldies need a filter check this article out.

As I have learned more about keeping fish I know I screwed up.

If I had added a filter this would have increased their chances of survival but I really should have let the water cycle first (more on that later).

Fish are living creatures the pee and poop just like all of us. This has to go somewhere!

Would you like to swim in your own excrement?

Didn’t think so.

A tank filter like the EHEIM Classic 250 will remove excess food, decaying organic matter, free-floating particulate, dangerous chemicals, and the fish’s waste products from the water.

When you choose a goldfish tank filter you are faced with a choice an internal filter or an external. It’s pretty self-explanatory, one sits in the tank and the other outside.

I prefer the external because they contain more filtration media and therefore do a better job of cleaning your water. You can also tuck the filter out of the way in a cabinet to make your tank look better and less cluttered.

Now if your tank is 20 gallons you want a filter that is able to filter 10 times the amount per hour.

So you would want a 200 gallons per hour filter for this tank.

What Is The Best Goldfish Tank Temperature? 

Caring For GoldfishGoldfish are pretty hardy creatures but you should still strive to create the perfect environment for them.

So what is the best goldfish tank temperature to keep our goldies happy?

The ideal tank temperature for goldfish is around 60-75 degrees Fahrenheit.

The problem with goldfish is they hate inconsistency. So if your tank is continuously changing temperature you will end up with unhappy fish.

Choosing a large tank is better to keep the water temperature consistent enough for goldfish. If you do notice your temperature is fluctuating, you might consider a heater with a thermostat and set it to the correct temperature.

In most cases, you will not need one though.

What Is The Best Fish Tank Substrate For Your Goldfish?

The tank substrate is basically the tank floor and it is the first aqua-scaping decision you will have to make.

Choosing the best fish tank substrate will help keep your goldfish happy and safe in their environment.

With goldies they are pretty happy with most to be fair but here are my takes on each.


Aquarium GravelGravel is probably the most common substrate for most new fish owners. It comes in a variety of colors and makes it look funky and cool.

Now it won’t affect your fish directly but food and excrement can get stuck in the gravel. This means you will have to be more vigilant with your tank cleaning schedule.

On the other side of the coin, gravel will hold on to good bacteria too.

But unfortunately, the bad bacteria is too harmful!

Goldfish are big waste producers and if this is trapped in the gravel at the bottom, the tank will become a pool of bad toxins.

Over time this will take its toll on your little buddies immune system.


Aquarium SandSand, in my opinion, is a much better choice for your goldfish tank. Some people have actually said that a fish ingesting a little bit of sand is good for there digestion.

Healthy fish equals happy fish!

Sand went out of fashion as people claimed it irritated the little dude’s gills but this was later disproved.

Wild goldfish swim in muddy, sandy rivers so why shouldn’t our domesticated fish?

The only problem is the appearance it’s not as pretty as blue, white and green gravel. In my opinion, though, it looks more natural.

And your goldfish will love to dig around in it also.

For waste, sand is great as it will actually just sit on the top. Not as great to look at but with a little vacuum your tank will be much better for your fish.

This all means a lot fewer toxins.

No Substrate

When you attempt to breed goldfish it is recommended not to put a substrate down. This keeps the water quality perfect for the arrival of the babies.

It also keeps your fish free from substrate related injuries, such as ingestion.

The only problem with a bare bottom tank is aesthetics. It’ doesn’t look as great. Having said this, goldies thrive a lot more in a substrate-less aquarium.

Place some rocks with live plants attached or set the rocks on goldfish approved plastic plants.

Wood is another option just make sure that you let it get used to the water or you could end up with a tan colored aquarium.

Decorating Your New Tank

When it comes to decoration or aqua-scaping you have full control. The only thing you need to be sure of is… is it safe for your goldfish tank?

Caring For Goldfish

Most aquarium dealers in your area will only stock safe decor. If you are buying online make sure you buy from a reputable retailer. Look at reviews and see what others think before you dive in and buy your tank ornaments.

I prefer to keep things looking natural so I tend to go for plants, rocks, and wood. I also live by the less is more saying. You do not need every area of the aquarium to be covered with decor.

Clutter reduces the amount of room your fish has to swim in. Do I need to remind you how important space is for goldfish?

For me, I would settle for a bit of wood that has loads of areas for fish to swim through and hide.

I would maybe add some rocks too.

Going minimal and natural is a lot more fresh and clean looking. I totally love the natural look but if you see a goldfish safe Nemo or Dory then go for it!

Do You Need Plants For A Goldfish Tank?

When you are choosing plants for your goldfish tank you must check that they are safe for goldfish.

Goldies love munching on plants, it adds variety and adds variation to your goldies diet.

For this reason, you should buy fast growing plants. Slower growing plants might not get the chance to grow.

Goldies love having a little nibble… ok, a big nibble!

You just need to remember goldies love to dig around in the gravel and this could lead to the plants being pulled out and left floating at the top. Not a big problem though, just attach to your rocks or wood.

Weighing them down will keep the plants in place.

So what plants work well for your goldfish aquarium?

Anacharis Plant

Anacharis PlantThis is a hardy beast and perfect for your first goldfish tank. It is very fast growing so no chance of your goldfish eating before it grows.

In cold water tanks, it doesn’t need a fertilizer or substrate supplement, so it is extremely low maintenance. You may have to cut back or prune though.

It works well being buried in the substrate or free flowing.

Lastly, anacharis is a great plant for boosting oxygen levels within your tank and absorbing excess nutrients and minerals.

Java Fern

Java FernJava fern is another easy plant for your goldfish tank and looks great too. This one is a hardy plant but has a bitter taste, so your goldfish will not be as fond of this one.

However I am sure they will give it a go.

This is a great plant for no substrate setup as it will not root!

Weigh it down with a rock or driftwood and it will thrive. If you do notice it wilting it could be due to the sunlight.

Bright conditions are not great for Java Fern, moderate light is best.

Now that you have a couple of plants and decorations it is time to get the water ready for your goldfish tank.

Adding Water To Your Cold Water Aquarium

So far you have done so much to prepare for your new friend’s arrival. His new pad will be looking awesome but you still need to add the main part of his environment.

The water.

The trouble is that tap water contains chemicals to make it safe for us to drink. These chemicals are just too much for your new goldfish though. This doesn’t mean you have to go buy fancy bottled water for your goldies.

You just need to treat it to make sure it is fish safe.

There is a wide variety of water treatments available to soften tap water and make it safe for our fish. These can be sourced from most pet shops or aquarium suppliers. It isn’t too expensive either.

I use Tetra Aquasafe Plus.

This does a fantastic job of neutralizing chlorine, chloramines, and heavy metals. That’s not all it does for your tap water, it also adds minerals and vitamins.

If your goldfish has been in harmful water then they may have damage to them. Tetra AquaSafe Plus will also rebuild their slime coats and boosts the growth of beneficial bacteria (essential for keeping your aquarium water healthy).

You can pick this up on Amazon, click here to see the best price!

Another great choice is SeaChem Prime, I haven’t personally used this but I have heard really good things about this from friends.

It works by removing chlorine and chloramine in tap water and then converts harmful ammonia into a safe, non-toxic substance.

Before you fill up and add your little friends you need to be aware of the nitrogen cycle. Your water still is not ready for your goldfish.

The Nitrogen Cycle: It’s A Matter Of Life or Death

Great your tank is set up. It is time to add your new buddies…


You need to cycle your tank first…


This is something that should be done before you add any fish to your tank. Having said that I have heard of people using hardy fish to cycle their tanks.

The safer method is to do it the fishless way. If your water and filter are not ready for your new fish you could be sending them to an early grave.

When you cycle your tank you are basically building a colony of good bacteria to help keep your water safe for your fish. Fish pee and poop leave toxins in the water.

Ain’t no fish got time for that!

These toxins include ammonia which is super dangerous for your fish.

The good bacteria will change this to nitrite but this still isn’t great for our little buddies. Lastly, the Nitrobacter bacterium which will convert the nitrites into nitrates.

This isn’t that safe either but it is only harmful in extremely large quantities. Your tank goldies should be comfortable with some nitrates.

Ok… So how do we actually cycle our tank?

Well, you have your tank set up, so turn on the filter and add some ammonia.

Then just test the water until the readings state that there is zero ammonia, zero nitrites, and a few nitrates.

This sounds more difficult than it is. Here is my six step tank cycling process…

Step One: Turn on the filter and add good bacteria (such as Top Fin’s Beneficial Bacteria) and let the water sit for about an hour.

Step Two: Add one drop of ammonia for every gallon of water in your tank. You will need to do this daily until the tank is safe.

Step Three: Test daily! It is normal to see a big spike of ammonia in your first water test in the early stages. Do this daily until you see some nitrites. Once those bad boys show up you are on the final leg. You are looking for nitrates now.

As time goes on the ammonia and nitrites will zero out but you should still add the ammonia until the day before you get your new fish.

Step Four: Do a 50-90% water change… This might sound like a waste of time. You have added all that ammonia and now we are changing the water.

You have built up the good bacteria in the filter media now. When you change the water and treat it to be fish safe the good bacteria is still present in the filter.

Step Five: Wait 24 hours after the water change!

Step Six: Add your fish 1-2 at a time. Adding too much at once will cause the ammonia levels to be too high for your good bacteria and your new goldfish.

IF you want to skip right ahead you could ask someone to give you some of their goldfish tank filter media.

That is if you know it is safe!

After doing this leave for a few days to a week and check the levels daily. You still need the bacteria to be established before you add your new fish.

Are You Ready To Start Caring For Goldfish In Your Snazzy New Tank?

Now you know how to setup your first tank it is over to you.

Remember tank size is super important. The more space you give your new buddy the happier it will be. Plus you need to give it room to grow.

Remember to judge the size based on all the inhabitants even the tank mates.

Never underestimate water quality, if you screw this up… you could kill your fish.
Frequently test your water to make sure that the quality is acceptable.

A healthy fish is a happy fish and a fish that is full of character is a hell of a lot more fun than a sick fish.

I hope you have enjoyed my caring for goldfish guide, it’s time to take action and set up your dream tank…