The Proper Care of Goldfish
The humble goldfish
It's considered a good 'starter pet' for children. Goldfish are sold in pet stores and have traditionally been given away at fairs.
They are considered 'easy' fish to keep, but the truth is that most pet goldfish do not live that long. 'Fair' goldfish are particularly notorious for dying within a few days.
Most people do not know that goldfish can grow up to a foot long and can easily outlive you. Very few pet goldfish reach that size or age, however. But you can avoid a rapidly dead goldfish and a crying child fairly easily.
The traditional goldfish bowl needs to go away. It is too small a container for a goldfish to be happy and healthy in. Remember that your goldfish is breathing the water and the water in a bowl becomes stale quickly. The most common reason for a goldfish dying a few days after acquisition is that somebody tossed it in a bowl...and didn't change the water.
If you want to keep goldfish indoors, then they are better off in an aquarium. Goldfish need quite a bit more water than you think. Also, that tiny goldfish is probably a very young fish - it will grow. The pet goldfish I had made it to about six inches and would probably have grown bigger if they hadn't spent their winters in a fairly small tank.
Goldfish can also live outdoors in a pond in many climates. They can handle temperatures between 40 and 105 F. If your winter water temperature would regularly drop below that, then bringing them inside for the winter should be considered. Goldfish are good pond fish because they do not graze and will not eat your decorative plants.
The Right Water
The other way people kill goldfish is to fill the bowl or aquarium directly from the tap.
No fish should ever be kept in plain tap water. The chemicals we use to kill bacteria and make the water safe to drink are highly toxic to fish.
There are two good alternatives. The first and most common is to use an aquarium water conditioner. This neutralizes the chemicals and makes the tap water safe for your goldfish.
A second alternative, although not one everyone can do, is to use a rain butt and fill the tank from that. It's my opinion that goldfish prefer their water 'natural', but apartment dwellers and people in desert areas may not have this option, nor do those in the far north in the winter. On top of that, many states have made harvesting rainwater for any purposes illegal. You may need to get a permit for a rain butt. (I consider this a very unfortunate situation, but it would be off topic to go into it).
Cleaning and Changing Water
If you keep your goldfish in an aquarium, then you need to change out half the water every week. With practice, this can easily be done without disturbing or moving the fish.
It's also a good idea to use a gravel cleaner to collect the muck that tends to settle in the bottom of the tank...this is a mixture of shed scales and fish poo and it is inevitable. If you have very small fish in the tank, be careful. People have been known to vacuum them up.
The old water should be siphoned off carefully and the fresh water added slowly.
Keeping the tank cover on most of the time will also help to keep the tank clean. Goldfish aquariums are also notorious for collecting algae. If there is not that much algae, then leave it - the fish like to eat it and it helps make sure they get enough fiber in their diet. (If you find a goldfish floating upside down, they probably need more fiber...constipation can throw off the balance of their swim bladder).
The best way to control algae growth is to clean the tank regularly and not to overfeed your fish.
Another common goldfish care mistake is to over-feed your fish. This increases the risk of excessive algae growth in the tank and of your fish getting constipated.
Left over food can also cause water quality problems including ammonia levels that can poison your fish. If your fish don't clean up all of the food you give them within a couple of minutes, then you need to feed less. It's normal to feed goldfish only once a day.
Goldfish can survive on flakes, but they will not thrive on them. Always feed flakes designed for goldfish, not other species. As omnivores, they will appreciate some variety in their diet. Spirulina is an excellent food for goldfish. Your fish might also appreciate some vegetables or fruit and peas are particularly good for them.
A fish that's gasping at the top of the tank is not begging for food - it's either filling its swim bladder or, if it goes on for too long, short of oxygen - the water may need to be changed.
Avoid fair goldfish. (I had one that lived a happy and healthy life for many years, but this is the exception, not the rule. They are often in those plastic baggies for far too long and under a lot of stress).
Go to a good aquarium store, preferably a specialist or, if you can find one, direct to a breeder. Bring your goldfish home as quickly as possible. The less time your fish spends in a bag, the better for the fish. Keep the bag covered...ideally put it inside a box. Remember fish cannot close their eyes.
Open the bag immediately when you get home, then place the bag in your aquarium for 10-15 minutes...this lets the water temperature equalize before releasing the fish. The fish will appreciate being allowed to quietly explore its new home.