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Information about fish for potential fish owners

Information about fish for potential fish owners

Pet fish of various varieties make popular and interesting pets for all sorts of people, and there certainly is a lot to recommend fish keeping to animal lovers of all types and ages! A fish tank can provide a focal point in a room that is even more engaging to watch than the TV, is relatively low maintenance depending on the type of tank that you keep, and offers the perfect alternative to furry pets for allergy sufferers and those who are not keen on mammals!

Domestic fancy fish within the UK can be kept outdoors in a pond (which is suitable for coldwater fish such as Koi Carp and goldfish) or indoors in an aquarium or tank. Fish kept indoors in an aquarium are divided into three broad categories: coldwater, tropical and marine. How indoor and outdoor fish are kept is understandably rather different, and in this guide we will concentrate on advising people who are seeking to keep pet fish indoors. More information on keeping Koi Carp and other fish in an outdoor pond can be found in this additional guide, here.

Although it might seem at first glance that “a fish is a fish is a fish,” there are in fact significant differences between coldwater, tropical and marine fish, and they all require different types of care and levels of commitment from the people that own them.

Would fish be a good pet for you?

Fish are a good pet for a broad spectrum of people, and are often able to be kept even in rented accommodation that does not allow other pets. Some of the most visually impressive and beautiful fish tanks are those populated with marine fish and coral, but the beautiful appearance of these tanks comes at a high cost, both in terms of money and the time taken to set up and care for them. Even if you simply want to keep a small goldfish or two in a bowl, the days when it was considered appropriate and responsible to come home with a small plastic bowl, some gravel, a pot of fish food and a fish in a bag, throw them all together and sit back and watch, are long since over.

Even the most low maintenance of fish require daily feeding, the correct housing and equipment and adequate care, and while it would be hard to think of an animal that was more low maintenance than the humble goldfish, nevertheless, they are still not a “feed and forget” pet.

If you are considering buying fish of any type, ask yourself the following questions:

  • Are you prepared to spend a significant amount of time learning about the fish you want to keep and establishing everything that you need to know about them beforehand? This can take anything from a few days to several months!
  • Are you financially able to provide everything that your fish will need to thrive?
  • Do you have enough time to dedicate to feeding and caring for your fish, and cleaning out the tank?
  • Are you allowed to keep fish within your home if you live in rented accommodation, and will having fish pose a problem if you need to move house?
  • Are the rest of your family happy with the idea of you having fish, and are you sure that younger children will be both safe around the water, and not pose an inadvertent danger to your fish themselves by playing around with the tank?
  • Do you have a suitable place to situate a tank within your home, including access to power points, enough room to keep equipment and move around when cleaning the tank with ease, and that is reasonably close to a sink?

You should be prepared to answer all of these questions and more before going forwards!

Coldwater, tropical or marine?

As mentioned, aquariums generally fall under three sub-headings: coldwater, tropical and marine.

  • Coldwater aquariums and tanks are those that are able to thrive indoors in the UK without a special tank heater, and can contain goldfish and a few other small breeds of fish that are hardy and not overly susceptible to the cold.
  • Tropical aquariums open up a much wider variety of fish in a whole rainbow of colours to the potential fish keeper, but need their tank to be maintained at a consistently warm temperature by means of an integral heater.
  • Marine aquariums are highly complex and fragile ecosystems in their own right, which represent a big step up from tropical and coldwater tanks in terms of their care requirements, cost, and the essential equipment needed to keep them. Marine fish, coral and invertebrates come from the warm water oceans of the world, and not only require saltwater to survive, but also need stable heating to be present in the tank, special filtration systems, special lighting, aeration and much more besides.

How much does it cost to buy and keep fish?

While this will come down to many factors such as the size of the tank you are getting and how fancy and technical you wish to make it all, again, to provide even a rough guideline in answer to this question requires it to be divided up into coldwater, tropical and marine sub-sections.

  • Coldwater fish such as goldfish are cheap to buy; often just a couple of pounds each. They also require minimal equipment compared to other types of fish, and the range of tank sizes available mean that it would be quite possible to set up a small but adequate tank for a couple of goldfish for around £50-£75.
  • Tropical fish range in price from just a couple of pounds each up to £15-£20 or even sometimes more for larger, very colourful species of fish, and require a little more equipment and investment to set their tank up. Nevertheless, a small tropical setup for a few smaller fish should be achievable for around £200-£250.
  • Marine fish tanks are almost indisputably the most beautiful, vibrant and attractive aquariums available, but all of this comes at a high price! Marine fish vary enormously in cost, from around £15 at the bottom end of the scale up to several hundreds of pounds, and it would be almost literally impossible to set up even a very small and basic marine tank system, even buying second hand equipment, for under £1,000. Marine tanks usually cost several thousand pounds in total to set up and fully populate.

What kind of time commitment is needed to care for fish?

With the exception of marine fish, which really are in a league of their own in terms of their care requirements, fish are generally thought of as a very low maintenance pet. For tropical and coldwater fish, daily feeding and a thorough weekly tank clean and partial water change is all that will normally be required.

For marine fish, you will need to spend a significant amount of time in the initial stages of researching, buying and setting up your tank, wait several months for it to mature and stabilise, and then introduce fish and other life to it gradually over the course of several more months. Marine fish certainly are not the solution for those seeking instant gratification, and you will need to be prepared to be patient and play the long game in order to set up and populate a healthy marine tank. Even when thriving and fully established, marine aquariums usually require several hours of care and maintenance every week.

Keeping a marine tank may also make it hard for you to go on holiday or stay away from home for any length of time, as it can be very difficult to find another experienced marine fish keeper locally who will be willing to take care of your tank for you in your absence.

What do fish eat?

Different species of fish in the wild eat a wide variety of different foodstuffs, including algae, plants, other marine life and sometimes, other fish. In the UK, we tend to feed dried food flakes or pellets, and many different varieties of these are available for different sizes and types of fish. You may also wish to feed supplemental frozen food, such as larvae, bloodworm and krill, if these are suitable for the type of fish you keep.

Setting up the tank

It is not appropriate to buy a tank and all of the various equipment that you will need to go with it, and set it up and put your fish into it all on the same day. Before you can buy your first fish, you will need to set up and establish your tank itself, and allow time for the natural lifecycle of the tank to begin, and the bacteria required for filtration and breaking down waste to establish itself within the tank. This can take anything from a week or two for coldwater and tropical fish, up to several months for marine fish!

It is important to set your tank up and kit it out, plant any plants you may wish to add and allow time for it all to settle down and become established before you buy your first fish and bring it home.

Cleaning out the tank

As well as daily feeding, you will need to dedicate an hour or two each week to cleaning out your fish tank and partially changing the tank water for fresh. This will involve siphoning out some of the tank water and replacing it with fresh water that has been treated and de-chlorinated, and physically cleaning the tank itself.

Your fish should remain in the tank while you do this if at all possible; it is less disruptive to your fish to work around them than it is to move them to a different vessel while you perform essential maintenance. You will need to clean algae from the glass of the tank itself, clean any equipment in the tank, and remove any faeces sitting on the surface of the substrate with a siphon or other equipment. You will also need to clean out the filter, and generally perform a range of regular maintenance that will vary depending on the type of fish you are keeping and the equipment that you use to care for them.

Health and wellness

Fish are generally robust and healthy when correctly cared for, but may be prone to a range of illnesses and conditions if kept in unsuitable conditions, malnourished or incorrectly cared for. Fish illnesses and diseases are usually highly contagious when introduced into the tank, and when treating health conditions in pet fish, usually a treatment solution is added to the tank water rather than administered to any individual fish.

Some information on common fish diseases can be found here, plus an article on bacterial ulcers in fish is available here.

Keeping fish in an overcrowded tank is one of the fastest ways to reduce the water quality and introduce toxins and diseases, and you should carefully research how many fish you can comfortably keep in a tank of the size you are considering. This will vary depending on the type of tank you keep and the species of fish, and is normally presented as a ratio of the body length of all of the fish to the total volume of water in the tank. You may be surprised to learn quite how much space fish need in order to thrive and be at their best, and good advice to follow is to always buy the largest tank that you can afford, both in terms of space and money.

When browsing for fish in a pet shop or viewing fish offered for sale by any other seller, here are some pointers and indicators of poor health to look out for and avoid.

  • Fish kept in dirty or overcrowded conditions are much more likely to be prone to contracting diseases and illnesses, so only buy from retailers that house their fish appropriately and properly care for their upkeep.
  • Never buy even a healthy-looking fish from a tank where another fish is dead or dying.
  • Floating on the surface of the water indicates that a fish is dead, however shortly after death, they may be laying near the bottom of the tank.
  • Any fish with visible injuries should be avoided.
  • A fish that appears to have problems with buoyancy, is swimming oddly, or that appears to have problems remaining upright should be avoided.
  • The fish’s scales should be smooth and flat, with no missing or damaged scales.
  • The fins and tail should be intact and not appear ragged or damaged.
  • Never buy fish from a tank where any of the occupants appear to have any fungus, spots or other growths on their scales.

What kind of equipment do you need to keep fish?

Regardless of what type of fish you are planning to keep, you will of course need a tank of the appropriate size, and potentially a suitable sturdy stand to place it on! A fish tank full of water is extremely heavy, and while you may think you have identified a suitable work surface or table to place your tank on, you should be particularly careful to make sure that it will be able to support the weight of your full tank in order to avoid a disaster!

It may also be worth bearing in mind the structural integrity of your flooring if you plan on keeping a very large tank on a level above the ground floor of your home.

In order to keep marine fish, your shopping list of equipment will be detailed and very specific. A full list of equipment needed to keep marine fish, as well as a lot more information on their housing and care, can be found in this article.

In order to keep coldwater or tropical fish, you will need most or all of the following items:

  • A tank
  • A stand for your tank
  • A lid for the tank
  • Lighting for the tank
  • For tropical fish, a heater and thermometer
  • A magnet to clean the tank glass
  • Substrate for the bottom of the tank, such as fish-suitable gravel, sand or pebbles
  • A means of filtering the tank water, which can come in various different forms
  • Plants and hiding places for your fish to rest in and snack on
  • Ornaments and other “furniture” for the tank
  • Water treatment agents
  • Nets, buckets, a siphon and other cleaning equipment
  • Air stones or other means of aerating the water
  • A water quality testing kit
  • Some basic fish disease treatment products
  • A good guidebook on fish care and how to identify signs of illness

A note on filtration

Up until as recently as five or ten years ago, it used to be relatively uncommon to find water filters used within small goldfish bowls and tanks, and goldfish were often kept in very small tanks and bowls with no filtration at all, other than that which was provided as part of cleaning the tank and performing partial water changes.

Goldfish kept in these conditions rarely thrived, and few lived past the three year mark. Filtration is considered to be necessary for fish of all types and sizes, including the humble goldfish, and you should not seek to cut corners in the cost of setting up your tank by leaving out a filter. Fish produce a significant amount of waste comparatively to their body sizes, and living in dirty, unfiltered stagnant water will soon affect the health and shorten the life of your fish.

Where and how to buy fish

Fish of different types are widely available to buy from places such as pet shops and even garden centres, and specialist fish-only stockists such as those that specialise in marine fish. You can also buy fish privately from specialist keepers and breeders, and even private owners who find that their own fish have bred and that their tanks are becoming too full!

Check out some of the fish for sale and fish for adoption offered by third-party sellers here on Pets4Homes.

When looking at a selection of fish for sale or adoption, first of all consider the environment in which the fish are kept, and if you are satisfied that the seller takes pride in their tanks and cares about the welfare of their fish. Check the fish being offered against the “health and wellness” checklist covered earlier on, and ask the seller everything you will need to know about the care, feeding and maintenance of the fish on offer.

Make sure that you get a receipt for any fish that you buy, and find out what comeback you will have on the seller if the fish die or show signs of illness soon after returning home.

How to transport your fish home and settle them in

Fish are undoubtedly one of the most challenging types of animals to transport and move around, for obvious reasons! When you buy your fish, they will normally be caught for you by the seller, and packaged in water from their own tank into a clear plastic bag for the journey. You should buy your fish as near to your home as is feasibly possible, to minimise the length of time that your fish will be in transit. There are two issues to address when transporting your fish home: keeping their temperature stable, and keeping their bag or container upright and minimising movement.

  • Take along a box or container of some type that contains some padding such as bubble wrap that you can place the bag containing your fish in, both to keep the bag upright and stable and to help to keep the temperature of the water constant for as long as possible.
  • Ensure that the container holding your fish is secured within the car, and drive carefully and smoothly.
  • When you arrive home with your fish, your tank should be already set up, acclimatised and settled, and ready to receive your fish.
  • Turn off the main light in the tank before you begin.
  • Float the sealed bag containing your new fish in the water of your tank.
  • After ten or fifteen minutes, the temperature of the water in your fish’s travelling bag should have begun to acclimatise to match the water in the tank. At this point, open the bag, and introduce a little bit of tank water into the travelling bag.
  • It is important that you add tank water to the bag that your fish is in and try to minimise the amount of water from the bag that enters your tank, as this will reduce the chances of any water-borne nasties or infections from the water in the bag entering your own tank.
  • Gradually continue to introduce more of the tank water to the bag every ten minutes or so, until the volume of the bag is 50% or more filled with water from the tank itself.
  • At this point, your new fish should be ready to enter your tank.
  • Do not simply tip the whole bag containing water and fish into your tank; as mentioned, you should try where possible to keep the bag water out of the tank itself.
  • Use a net to remove your fish from the bag and place them into the tank, then promptly remove the bag of water and tip it away.
  • Leave the tank lights off for the remainder of the day to allow your new fish to settle into his home comfortably.
  • Wait until the following day to start the daylight cycle with your tank lights, and to feed your fish.