Goldfish Care Guide

New fishkeepers are often shocked to discover that what’s stopping 30 gallons of water from spilling across their carpet is simply glass and glue, which is all that modern fishtanks are made out of.

Fear not, silicon glue is immensely strong, and compared to the old wrought-iron or putty-framed fishtanks of yesteryear a well-made all-glass aquarium is far less likely to leak. Acrylic (also known as ‘plastic’) tanks are even more robust, being fashioned out of one molded piece of material. They’re quite expensive compared to glass though, and they do tend to scratch rather easily.

What else do you need? Goldfish have been kept in little more than watertight vessels with gravel on the bottom for hundreds of years, so technically the answer is ‘nothing’. However there are various bits of equipment that will make keeping your goldfish healthy much easier.

Let’s consider what equipment you need for an ideal goldfish aquarium.

The fishtank

Get the biggest goldfish tank you can afford and fit comfortably into your house. Goldfish can grow quite big, and some varieties such as Common and Comet goldfish really like to swim, so they appreciate room to stretch their fins.

Just as importantly, coldwater fish like goldfish require lots of oxygen in the water, which means you can’t crowd too many into one aquarium. If your tank is too small, you’ll be limited to keeping just one or two fish. Frustrated, you may be tempted to add too many, which is where the problems start…

A tank of two-foot in length is the minimum size we recommend for goldfish, with a width of at least a foot. The tank can be as tall as you like, but keep in mind a taller tank doesn’t let you keep any more fish, as we explained in our How many goldfish can I keep? article. Tall aquariums do look pretty though.

If you can get a three- or four-foot long tank, so much the better. Your fish will be happier, and you’ll be able to keep a nice shoal of fish. One of the delights of goldfish is watching them interact, so we always like to have a few per aquarium if possible.

Air pumps and airstones

You can blow bubbles into your fishtank using a device known as an air pump. The effect is very attractive, and fish seem to prefer moving water. Most importantly though, such circulation increases how much oxygen your tank water holds, by moving old water to the top of the tank, and by creating ripples in the surface water that helps with oxygen exchange. Using a pump can therefore increase how many goldfish your tank can hold, although we generally prefer to stick to the normal levels and have an extra margin of safety. If you do keep more fish, be sure to leave your pump running 24 hours a day.

Aquarium filter

Filters aren’t strictly vital, but they do make keeping goldfish much more enjoyable. A good filter will keep the water clean by straining out particles, and it will also purify the water biologically, which removes the toxins created by the waste products and leftover food of your goldfish. For more information, read our article on the types of aquarium filter.

Lighting

A bright lighting unit over the aquarium is a must. Not for growing plants (goldfish soon devour most of them, unfortunately) but to help you see your pets! Specially-made florescent tubes are ideal for our purposes, and come tweaked to show off the colours of your fish. Don’t be tempted to use ordinary units from the hardware store unless you really know what you’re doing; water and electricity is a deadly combination.

The aquarium substrate

Bare-bottom tanks look very unnatural, so you’ll want to put a layer of gravel or sand in your tank. Aquarium gravel comes in all shades and tones, and provided you buy it from a reputable store it’s really down to your personal taste what you use. We recommend small-sized natural coloured ‘pea’ gravel. It looks good, and it isn’t as likely to go ’stale’ as sand. Keep gravel to about an inch in depth, unless you’re using an undergravel filter.

Special bogwood, plastic plants, treasure chests and so on

Your fish store will have whole shelves devoted to decorations for your tank. Most cost more than the fish, and so many retailers dedicate more space to furnishings than to goldfish! Again, provided you’re buying your decorations from a decent shop, it’s down to you what you choose for your aquarium. Don’t put unknown stones or other objects into an aquarium, since they may introduce toxins that are harmful to your fish.

We’d suggest a few clumps of plastic plants and a smooth stone or two, together with a nice gnarled piece of waterlogged bogwood, but if you want your goldfish to live in a multi-coloured Disney World, don’t let us stop you. The fish won’t mind, but do be sure to leave enough room for them to swim about.

Heaters

These aren’t required for indoor goldfish aquariums, and you should be highly suspicious of any retailer who tries to sell you one.

Please make sure you read our guide to setting up your goldfish tank to learn how to put all these items together. Your tank should be filled with water and up-and-running for a couple of weeks before it holds any fish, and you should build up to the maximum number of goldfish gradually.

Filed in: Care, Equipment