Nicola's Fishies: Goldfish Care

On this page I've written some tips and advice on keeping goldfish.  The sections I've written are:

• What Goldfish Need
• What You Need for an Aquarium
• How to Not Kill Your Goldfish When You First Get It
• Symptoms of Disease

What Goldfish Need

Goldfish will always live best in an aquarium or pond. A lot of people think goldfish live in bowls, but they need the space and oxygen that an aquarium or pond provides. People also may think that goldfish have short lifespans, but the truth is they can live 20 or more years in prime conditions. Here is what goldfish need to be healthy:

• Goldfish need space! If you get one or two small goldfish, a small aquarium (2 gallons, 5 gallons) will be good while they're small. Aquariums are better than bowls because they can provide space, aeration, and filtration.

  A 10 gallon aquarium is the smallest standard-size aquarium you can get. Here's what it looks like:

  • A 10 gallon aquarium with no fish and few decorations.

  If you want to have a bunch of goldfish, or want something that will suit your fish all their life, you can get tanks of 20 gallons, 30 gallons, 50 gallons, and more. The general rule for goldfish a couple years old is 10 gallons per fish.

• Goldfish need oxygen. Stagnant water in a bowl does not give them enough oxygen. Goldfish spend a large amount of time at the surface in a bowl not because they're hungry, but because they can't breathe! So make sure you have something that increases oxygen in the water, such as an air stone. (Goldfish also love swimming through the bubbles. :-)

• Goldfish need safe water. That means the water should be 1) non-toxic and 2) at the same temperature the fish were in before. (Goldfish can live in very cold water, but a sudden temperature difference will shock or kill them.) Goldfish bowls need a complete water change every week, whereas aquariums need 10% of the water changed every week (or so).

  Aquariums need to cycle before they are safe for fish to live in. Here's a page which describes the nitrogen cycle. Basically, if you're setting up an aquarium, you need to properly cycle it before it's safe for fish to live in.

  For the water to be safe, you need to leave tap water out overnight to allow chlorine and other chemicals to evaporate. (Don't use distilled water, because the fish need certain minerals in tap water.) You can also add a dechlorinator to the water, such as AmQuel, AquaSafe or Stress Coat. Salt (such as kosher salt or aquarium salt) is unneccesary but can be helpful to the fish's slime coat and to kill parasites.

  Use decorations labeled aquarium-safe; anything else is at your fish's risk. Some decorations can slowly release toxic chemicals you're not aware of. Try to avoid washing decorations (or your bowl/aquarium) in soap. Hot water and scrubbing usually works well. If you do use soap, only use it on glass things, and be sure to rinse it well.

• Goldfish need food. Goldfish like to eat a variety of food, just like people. They may like some types of food more than others. You will want to buy a staple food and occasionally feed them plants; they also love various freeze-dried or live foods. Goldfish are used to scavenging for food all day (that's why they look hungry all the time), so nibbling on plants or eating small meals twice a day works well for them.

  Staple foods come in flake and pellet forms. Find a good quality brand for your staple food, such as Hikari, Omega, ProGold, or BioBlend. A quality food will have a variety of plants and whole animals in the ingredients, and vitamins. You could have two different brands, one cheap and one quality, to even out the price and provide some variety.

  Goldfish enjoy eating plants and get nutrients and fiber out of it. Plant material is needed for good digestion, especially for fancy goldfish who are more prone to swim bladder disease. (One common cure for swim bladder disease is to feed them peas.) To feed them leafy plants and other foods that you want to keep in place, you can purchase a veggie clip, which is a plastic clip with a suction cup on it. Some plants they can eat are:

  Vegetables (steam or soak in hot water):

  • dark green leafs such as romaine or spinach
  • peas (deskin)
  • cucumber
  • zucchini
  • carrots (mush lightly)
  • corn (deskin)

  Other plants:

  • anacharis/elodea
  • spirulina flakes
  • algae flakes

  Fruits (peel and cut up, do a water change later):

  • grapes
  • oranges
  • plums
  • cantelope
  • watermelon
  • grapefruit

  Other:

  • hard boiled egg white, some egg yolk

  It's also good to give them some freeze-dried, frozen, or live foods as well. Here are some examples:

  Freeze dried and frozen foods:

  • blood worms (mosquito larvae)
  • tubifex worms
  • krill (large shrimp)
  • brine shrimp

  Live foods (watch out for pesticides and diseases):

  • earthworms
  • blood worms
  • brine shrimp
  • tubifex worms

What You Need for an Aquarium

So, you've decided you want an aquarium... now what is all that stuff you need? Well, the easiest way to get most of what you need for an aquarium is to buy an aquarium kit. However, it may not come with the most quality items. :-/ To help you out, here is a list of things you'll need.

Stuff you need:

• An aquarium. Choose the size that will best house your fishies. If you get a rectangular, standard-sized aquarium, decking it out with other stuff later will be easier. (If you get a bowfront one, you may have trouble replacing or adding things.)

• An aquarium stand. A desk or other piece of furniture may not be able to hold the weight of a full aquarium. They make aquarium stands that can hold two aquariums, which I like for space reasons.

• A lid. You need a lid to keep fish from jumping out (very sad :-( ), and to keep evaporation down. Glass lids are easy to clean. They have a plastic strip in the back that you can cut away for your aquarium things.

• A filter. There are three kinds of filtration: mechanical filtration, which is the netty/flossy part that catches poop and other stuff; biological filtration, which is where good bacteria grow; and chemical filtration (optional), which uses carbon to filter out chemicals like a Brita water filter.

  A power filter does all three. It hangs on the back of your aquarium and sucks water through a tube to its filter cartridges. You change the filter cartridges once in a while. There are also canister filters which sit inside the aquarium, and sponge filters which provide lots of space for good bacteria to grow, but won't suck up poop. (And goldfish poop a lot.)

• An aerator. This includes buying: 1) the air pump, 2) the airline tubing, and 3) the air stone/diffuser. I suggest getting an airstone with a plastic casing around it. Airstones will wear out or break after a while so you will be replacing them occasionally.

• A water siphon and a bucket for old water. This is how you do water changes. You stick the siphon in the water and swish it back and forth, and the water will start being sucked out. Work the tube down to the bottom of the tank in different places and get as much poop out as you can.

• A new water bucket. You'll need to leave water out so chlorine can evaporate.

• A fish net.

• An extra bowl or tank for quarantining fish. New fish are often sick.

Stuff you probably want:

• Gravel. Watch out for painted gravel that chips off a lot. This dirties the aquarium forever. I suggest natural-looking gravel, or gravel that looks like the paint won't chip so much. You can have a clear bottom tank, but the goldfish's national pastime is rummaging through gravel.

• Decorations. Goldfish eat real plants, so for decorating I suggest getting plastic plants. Glass stones make the gravel pretty. Decorations with big holes are fun for the fish to swim through. Just make sure all your decorations are labeled aquarium safe... otherwise you could unknowingly poison your fish.

• A gang valve. A gang valve will split your airline tubing into two or more connections, and have little handles so you can control the amount of the air.

• An algae scrubber. Keep the sides of your aquarium looking pretty. If you get too much brownish algae growing on everything, Siamese algae eaters sometimes work okay with comet goldfish. Snails are cute but don't do quite such a good job getting rid of all the algae. :-) (And they poop a lot if there's a lot to eat!)

• Water dechlorinator. If you leave your water out overnight, it should be perfectly fine, but if you don't have water on hand a dechlorinator will work. Some dechlorinators also add to the slime coat of the fish, so if the fish is sick or injured, that can be useful.

• Kosher or aquarium salt. Not much is needed on a regular basis, but if a fish is sick or injured it can help kill parasites and add to their slime coat.

Some cool things:

• A florescent light. You can buy big plastic canopy lids that come with lights, but I prefer getting a glass lid and then putting a light strip on top.

• An aquarium background.

• A veggie clip (a plastic clip with a suction cup), to keep vegetables in place.

• Plastic suction cup thingys that can keep the airline tubing against the side of the aquarium.

Important note on setting up a new aquarium:

• Aquariums need to cycle before they are safe for fish to live in. Here's a page which describes the nitrogen cycle.

How to Not Kill Your Goldfish When You First Get It

When you get a goldfish, you have to realize that it could already be diseased. Read the various Symptoms of Disease to become familiar with them before you buy a fish. You will soon notice that most of the goldfish in a large tank are already diseased and sad looking. Look around at various pet stores to find those that look healthiest. You'll probably still go through a couple fish before you find some that live more than two weeks, but at least you'll know better than to pick one that is already a goner.

Now this I can't emphasize enough... be very careful about adding new fish to an already established aquarium, because you could end up killing your whole aquarium if the new one is diseased. The best thing in this case would be to have a quarantine bowl/aquarium. Put your new fish in quarantine the first week or two. If everything goes well, then you can transfer the fish to the aquarium, keeping the quarantine bowl/aquarium on hand. At the first sign of any disease, in any of the fish, put them in quarantine.

Another thing that kills fish: Stress. So, we want to be as gentle to the fish as possible. Once you get your fish home, put the plastic bag in the bowl/aquarium. (See the above picture.) You want the water inside the bag to adjust to the same temperature as the water in the bowl/aquarium (remember that big enough temp differences can kill them). Leave the bag there a couple minutes. When you're ready to free your fish, hold the bag in the water and cut off the top. Don't just dump the fish in, because you don't want to add the dirty water to the clean water. Scoop him out with a fish net.

So... your fish is finally free! Now what? Now you want to observe him for a while.

Some good signs: Your fish swims down to the bottom and stays in front. He swims around a little and maybe even pecks at some of the gravel. He'll probably go in the back a bit but later on he swims with the other fish (if you have other fish). If he starts swimming happy and looking at you, then that is great.

However, fish aren't always that happy. A lot of times they're scared, and the other fish in the aquarium get scared too. Goldfish are scared when they freeze in one place and twitch their fins. Generally, the fish should eventually start swimming around. If your new fish stays antisocial and hangs in the back for a few days, then quarantine it, because it may be ill.

Don't go rearranging everything in the bowl/tank when you add a new fish, because you want to keep the stress down. Wait a bit to do any remodeling. :-)

That's the best advice I can give on how to not kill your fish right away. Don't be discouraged if your fish dies within the next week or two, which often happens with goldfish. (You may not want to name them right away either, for that same reason. :-) Just keep trying, and learn what works best for you. Soon you'll have a bunch of happy, healthy fishies, and if you take good care of them, they may never get sick.

Symptoms of Disease

General signs of illness:

• Being antisocial - stays in the back, doesn't swim around happily (sometimes this is the only symptom before a fish dies!)
• Clamped fins - holds its top and bottom fins against its body most of the time

Common diseases you should check for often:

• "Ick" (ichthyophthirius) - white spots on the gills, fins or body
• Fin rot - edges turn black and rot, or disintegrate and shred
• Body fungus (columnaris) - whitish-gray clumps of fungus on the fins or body (a bacterial infection)

Other signs of disease:

• Swim bladder disease - when resting, turns upside down or on its side
• Dropsy - scales stick out, fish is bloated and won't eat
• Septicemia - red sores, blood streaks, or a rusty tint to the body or fins
• Popeye - cloudy, protruding eyes
• Velvet - tiny yellowish-white spots on the fins or body
• True fungus - fungus around sites of injury or infection
• Visible parasites
• It rubs itself against the bottom (probably from ick or velvet)
• It flips around strangely (probably from toxic water)

Signs it's going to die:

• It's sitting on the bottom
• It's having trouble breathing - breathes faster, stays by the bubbles
• It doesn't eat

Whenever a fish shows any signs of disease, you should immediately move it to a quarantine bowl/tank. That might not save the fish, but it should help protect your other fish if you catch it quickly enough.

The main cause of fish disease is dirty water. Dirty water includes water which is too high in ammonia or nitrites. Aquariums need to cycle before they are safe for fish to live in. Here's a page which describes the nitrogen cycle. Fish bowls need their water changed once a week (or more), and aquariums need partial water changes every week.

Another possible cause of disease is new fish that may be sick, plants that may be carrying something or decorations that may not be safe. Move those things out.

In terms of treating fish... make sure the water is clean and you understand the nitrogen cycle. Beyond that: I like using the Mardel brand of fish medicines. If you can't find Mardel or want to use another, make sure you buy a quality brand. A cheap brand will probably not work.

I think that Maracyn Two is the most useful medication. It is used for dropsy, septicemia, popeye, and fin rot (gram-negative bacterial infections). Maracyn is for gram-positive bacterial infections like body fungus. You can use both at the same time, and often times if your fish is sick with something else, it will develop a secondary bacterial infection, and the Maracyn products will come in handy.

For ick, velvet, or any other parasites, Maracide and CopperSafe are good products. For true fungus, Maroxy is a good product. There are some other Mardel products as well; ask your local pet store which product or brand would work best for you.

(Remember that these medicines often cloud the water [a lot!!], so use them in a quarantine bowl or tank.)

It's also useful to try kosher/aquarium salt for parasites or external injuries. Salt is good for healing fish, and kills many types of parasites. It's also good for the fish's slime coat. Buy salt that doesn't have any additives, such as kosher salt which is big and cheap. Add 1 tablespoon salt per gallon in the quarantine bowl or tank. Let the salt dissolve and then add your fish. You can either leave the fish in salt for a while, or after a while you can move it back into a salt-free quarantine bowl or tank, and hopefully that'll help. You may also want to add a declorinator that adds to the fish's slime coat, such as Stress Coat.

Swim bladder disease can sometimes be cured by either soaking all food before feeding, or giving peas for a while. To give peas, cook them, remove the skins, and smush them a bit. If the SBD isn't caused by diet, then there may not be anything you can do for it. (Some people do surgery on their fish in this case... see for example, here, here or here.)

Good luck fish parenting!

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