Can a goldfish live in a bowl?

No. SPCA New Zealand says goldfish should never be kept in a bowl, and the RSPCA says bowls and jars were not designed with fish welfare in mind. Goldfish make a lot of waste and can grow large, so they need a big, filtered tank: SPCA New Zealand suggests 75 litres for one fancy goldfish.

How long should I wait before adding fish to a new tank?

At least two weeks, the RSPCA says, using fishless cycling, and the Merck Veterinary Manual says the helpful bacteria develop in 4 to 6 weeks. Add fish when ammonia and nitrite both test at zero, and add only one or two at a time so the filter keeps up.

Do I need to treat tap water for fish?

Yes. The Merck Veterinary Manual says most city water contains chlorine or chloramine, which are toxic to fish and to the bacteria in the filter. Add a water conditioner to every bucket of new water, or for chlorine, the RSPCA says water can be left standing for 24 hours.

How often should I clean a fish tank?

Change part of the water every week, about 10 to 25% in an established tank, with a gravel clean, using treated water at the same temperature. Rinse filter media gently in old tank water, never under the tap. Test the water every one to two weeks once the tank is established.

Can two betta fish live together?

Not two males. RSPCA Australia says two male Siamese fighting fish will fight to protect their territory and should never share a tank. A single betta can live with snails or large shrimp, and some small peaceful fish in a tank of at least 40 litres, but that is not for beginners.

Does a betta need a heater in India?

Usually yes. RSPCA Australia says a betta's water should be held at 24 to 26°C with a submersible heater, which only a tank, not a bowl, can hold. Check a digital thermometer every day.

What should I do for my fish in a power cut?

Put a battery-operated air pump in the tank, stop feeding until power returns, and keep the water cool by floating sealed bags of ice in summer. If the cut lasts more than five hours, a City of Riverside utility guide suggests changing about a quarter of the water.

Why are my fish gasping at the top of the tank?

Usually low oxygen, often in hot weather, after a power cut or in an overstocked tank. The University of Florida extension service says gasping at the surface is a sign of oxygen depletion that needs emergency aeration. Turn on an air pump, then test for ammonia and nitrite.

New pet guide 16 min read

Aquarium fish care in India: a guide for first-time fishkeepers

Updated October 2026By PetymFacts checked against official sources on 21 October 2026

Quick answer

Start with a filtered tank of at least 40 litres, never a bowl, and run it with no fish for at least two weeks so helpful bacteria can grow. Treat tap water with a dechlorinator, test for ammonia and nitrite, and add only one or two hardy fish at a time once both read zero.

Feed small amounts two or three times a day, change part of the water every week, and keep the tank out of direct sun, because warm water holds less oxygen. In a power cut, run a battery air pump, stop feeding and keep the water cool. A fish gasping at the surface needs air now, and a fish vet decides any treatment.

Find a sitter to visit your home

Meet your sitter first, free
PAN-checked, first-aid trained
A photo every day
Pay through Petym, never cash

Are fish the right first pet for you?

Fish are quiet and suit small flats and people with allergies, but they are not a low-effort pet.

The RSPCA says fish have complex needs that take preparation, money, time and care, and that they cannot show their feelings as clearly as other animals, so problems are easy to miss. You need to check the tank every day, change water every week and test it regularly. Someone has to do that while you travel.

Fish can live a long time. SPCA New Zealand gives goldfish an average lifespan of 10 to 15 years, and the RSPCA says goldfish are known to live up to 25 years and some reach over 30 cm. RSPCA Queensland gives bettas, also called Siamese fighting fish, an average of 3 to 5 years.

Fish suit some homes that cannot keep a cat or dog. The Asthma and Allergy Foundation of America suggests pets without fur or feathers, such as fish, for people with pet allergies. In Indian flats, think about where the tank will stand: the Merck Veterinary Manual says the floor and stand must be strong, level and stable, because water is heavy, and the tank should be out of direct sunlight.

Which fish should a beginner choose?

Pick the fish first, then buy the tank for that fish, not the other way round.

Cool water, big tank
Common goldfish
Hardier than fancy goldfish, which selective breeding has made more prone to health problems. Slim-bodied goldfish can grow to about 30 cm and are better suited to a pond than a small tank. RSPCA (England and Wales)
Keep with their own type
Fancy goldfish
Slower, twin-tailed fish that often miss out on food if kept with fast, slim goldfish, so keep body types apart. SPCA New Zealand suggests a 75-litre tank for one fancy goldfish, plus 40 litres for each extra. RSPCA (England and Wales)
One per tank
A single male betta
Two males fight to protect their territory and must never share a tank. A betta needs a heated tank, ideally 20 litres or more, with low water flow and plants to hide in. RSPCA Australia Knowledgebase
Groups of six or more
Small shoaling tropical fish
Danios, tetras, rasboras and many catfish live in groups. The RSPCA says keep them in groups of six or more, or they may feel stressed and hide. RSPCA (England and Wales)
Wait
Not for a first tank: marine fish
RSPCA Australia says a marine tank's filter bacteria take about twice as long to establish, and advises talking to an experienced aquarist or fish vet first. RSPCA Australia Knowledgebase

Is a fish bowl fine for a goldfish or a betta?

No. The welfare bodies agree on this, and on several other common beliefs.

You may have read
A goldfish is happy in a bowl.
Myth
What the sources say
SPCA New Zealand says goldfish should never be kept in a bowl. The RSPCA says bowls, jars and children's tanks were not designed with fish welfare in mind. SPCA New Zealand
You may have read
A betta can live in a cup or a small vase.
Myth
What the sources say
RSPCA Australia says small tanks and bowls do not give a betta enough space for its physical and mental needs, and are too small for a proper heater. RSPCA Australia Knowledgebase
You may have read
Tap water is fine straight from the tap.
Myth
What the sources say
Most city water is treated with chlorine or chloramine, which are toxic to fish and to the helpful bacteria in the filter. Merck Veterinary Manual
You may have read
You can add fish the day you set up the tank.
Myth
What the sources say
The RSPCA advises fishless cycling for at least two weeks first, so the filter can handle the fish's waste. RSPCA (England and Wales)
You may have read
More food keeps fish healthy.
Myth
What the sources say
The RSPCA says underfeeding is better than overfeeding, because fish suffer more from poor water than from a lack of food. RSPCA (England and Wales)
You may have read
A mirror gives a betta exercise.
Myth
What the sources say
RSPCA Australia says a mirror makes a male flare constantly, which causes stress and exhaustion. RSPCA Australia Knowledgebase

What do you need before you buy any fish?

Buy and set up everything first. The fish come last, weeks later.

A tank of at least about 40 litres (larger than 45 by 30 by 30 cm). Bigger is better, and a wide tank beats a tall one because it has more surface for its volume. RSPCA (England and Wales)
A strong, level, stable stand or cabinet, somewhere easy to reach for feeding and cleaning and out of direct sunlight. Merck Veterinary Manual
A filter suited to the tank size. The RSPCA says no fish should be kept without a well set up and maintained filter. RSPCA (England and Wales)
For tropical fish such as bettas, a heater with a thermostat, plus a separate digital thermometer to check every day. RSPCA (England and Wales)
A water conditioner (dechlorinator) to treat every bucket of new water. Merck Veterinary Manual
Ammonia and nitrite test kits. The RSPCA calls them essential, not optional extras. A nitrate and pH test helps too. RSPCA (England and Wales)
A lid, which keeps out some pollution and stops bettas, which are excellent jumpers, from escaping. Leave an air gap above the water. RSPCA Australia Knowledgebase
A light on a timer for about 8 to 10 hours a day, switched off at night. RSPCA (England and Wales)
A siphon or gravel cleaner and a bucket used only for the tank. RSPCA Australia Knowledgebase
Real or artificial plants and cover from an aquarium shop, never collected from the wild. RSPCA Australia Knowledgebase
A battery-operated air pump with spare batteries, for power cuts. Riverside Public Utilities, City of Riverside (California)

How do you cycle a new tank and add the first fish?

Cycling grows the bacteria that turn toxic fish waste into safer nitrate. It is the step most beginners skip.

Day 1
Set up the tank, filter, heater if needed, gravel and plants. Fill with dechlorinated water and switch everything on. Merck Veterinary Manual
The next two weeks or more
Run the tank without fish (fishless cycling). Test the water every other day. You are waiting for ammonia and nitrite to rise and then fall back to zero. RSPCA (England and Wales)
Up to 4 to 6 weeks
The helpful bacteria develop on their own in 4 to 6 weeks. The tank is cycled when ammonia and nitrite read zero and nitrate is being produced. Merck Veterinary Manual
Bringing fish home
Choose fish with smooth, unblemished scales and fins and bright, clear eyes, from a clean tank with no dead fish and clear water. Merck Veterinary Manual
Adding them
Float the closed bag in the tank for about half an hour, move the fish in with a net, and throw away the bag water. Keep the light off for the rest of the day. RSPCA (England and Wales)
The first six weeks
Add only one or two fish at a time. Test for ammonia and nitrite every two to three days, and change 10 to 25% of the water often, with a gravel clean. RSPCA Australia Knowledgebase
Once the tank is established
Test every one to two weeks, and at once if the fish stop eating or behave oddly. RSPCA Australia Knowledgebase

What do the water quality words mean?

Poor water quality is the most common cause of environmental disease in fish, the Merck Veterinary Manual says. These are the words on the test kit.

Ammonia: The waste fish produce. RSPCA Australia says it is toxic at 0.1 ppm, and more toxic in warm water and at higher pH. Aim for zero. RSPCA Australia Knowledgebase
Nitrite: What the first bacteria turn ammonia into. Slightly less toxic, but still harmful. Aim for zero. RSPCA Australia Knowledgebase
Nitrate: The end product, much less toxic in low amounts. Weekly partial water changes keep it down. RSPCA Australia Knowledgebase
Cycling: Growing helpful bacteria in the filter before fish are added, so ammonia and nitrite are turned into nitrate. RSPCA (England and Wales)
Chlorine and chloramine: Disinfectants in city tap water that are toxic to fish and to filter bacteria. A dechlorinator removes both. Merck Veterinary Manual
pH: How acid or alkaline the water is. Tap water pH varies a lot between cities and borewells, so test yours. Merck Veterinary Manual
Partial water change: Replacing part of the water with treated water at the same temperature. RSPCA Australia suggests 10 to 25% a week in an established tank. RSPCA Australia Knowledgebase
Gasping or piping: Fish crowding at the surface gulping air: a sign of low oxygen that needs emergency aeration. University of Florida IFAS Extension

How is caring for a goldfish different from caring for a betta?

They are the two fish most often sold to beginners in India, and they need very different tanks.

	Need	Goldfish	Betta (Siamese fighting fish)
Water temperature RSPCA (England and Wales)	Cool water fish. The RSPCA gives 10 to 21°C; SPCA New Zealand gives 20 to 24°C as ideal	Tropical. A submersible heater keeping 24 to 26°C
Tank SPCA New Zealand	SPCA New Zealand: 75 litres for one fancy goldfish, plus 40 for each extra	Ideally 20 litres or more, 10 litres the absolute minimum
Filter RSPCA Australia Knowledgebase	An efficient filter is a must: goldfish make a lot of waste	A filter with adjustable, low flow
Company RSPCA (England and Wales)	Can live alone (RSPCA) or with other goldfish of the same body type	Never two males together. Snails or large shrimp can suit
Feeding RSPCA (England and Wales)	Goldfish food, not tropical flakes, with chopped peas or spinach as extras	Once a day, only what it eats in under two minutes
Lifespan RSPCA Queensland	10 to 15 years on average, sometimes far longer	3 to 5 years on average

Sources give different temperature ranges for goldfish. In an Indian summer the bigger risk is water that is too warm, so keep the tank shaded and the room cool.

How much and how often should you feed fish?

Small amounts, two or three times a day, of food made for that kind of fish.

The RSPCA advises feeding two or three times a day rather than once, giving only as much as the fish eat in two to five minutes, and adjusting the amount to the number and size of fish. SPCA New Zealand says goldfish should finish their food in under two minutes, and RSPCA Australia suggests a single small meal a day for a betta. Remove any food left over, because it rots and fouls the water.

Use food made for the species. The RSPCA says tropical flakes are the wrong food for goldfish because the nutrients differ, and suggests chopped vegetables such as peas and spinach for goldfish as extras. Bottom-dwelling fish need sinking food. Do not drop roti, rice or biscuit crumbs into the tank.

For trips, the RSPCA says someone responsible should check the fish and equipment every day, that tropical fish need feeding daily, and that meals should be measured out in advance with clear instructions, because carers tend to overfeed. Avoid holiday feeding blocks, which release a lot of food quickly that may rot. An automatic feeder still needs a daily check.

How do Indian summers and monsoon affect a fish tank?

Heat is the main risk. Warm water holds less oxygen just when fish need more of it.

The Merck Veterinary Manual says the warmer the water becomes, the less oxygen it will hold, and that sunlight on a tank warms the water and feeds algae. A University of Florida extension sheet adds that fish need more oxygen as they warm up, so a hot afternoon in May can leave a crowded tank short of air. The RSPCA warns that placing a tank by a window can raise the water temperature dangerously high.

Keep the tank in the coolest shaded part of the flat, away from windows, kitchens and the top of the fridge, and check the thermometer every day. Run an air stone in hot weather, keep the lid gap clear, and do not overstock. If the water climbs too high, the City of Riverside's utility advice for outages is to float sealed bags of ice cubes in the tank to cool it gradually, rather than pouring cold water in.

The RSPCA also warns that cigarette smoke and aerosol sprays can be toxic to fish, which matters in monsoon when windows stay shut and mosquito sprays come out. A lid helps keep some pollution out. Do not spray insecticide or room freshener near the tank.

What should you do in a power cut or a fish emergency?

Oxygen first, then temperature, then water quality.

If The power goes off
Put a battery-operated air pump in the tank, with fresh batteries and spares nearby. If your flat has an inverter, check whether it covers the tank's socket. Riverside Public Utilities, City of Riverside (California)
If The cut lasts more than five hours
With a battery pump running, change about a quarter of the water with treated water at the same temperature to keep the water safe. Riverside Public Utilities, City of Riverside (California)
If Feeding time during a cut
Do not feed. Most aquarium fish can go several days without food, and feeding raises their activity and waste, using up oxygen and building ammonia. Riverside Public Utilities, City of Riverside (California)
If Fish gasping or crowding at the surface
Low oxygen. Start emergency aeration at once with an air pump, then find the cause: heat, overcrowding or dirty water. University of Florida IFAS Extension
If Ammonia or nitrite reads above zero
Change water. The RSPCA says if levels stay high, change half the water daily until they come down, and feed less. RSPCA (England and Wales)
If White spots, ragged fins, raised scales, a swollen belly or odd swimming
Test the water first, because most fish illness is linked to poor water quality, then ask a specialist fish vet. Do not add medicines without advice. RSPCA (England and Wales)

What are the everyday rules for keeping fish healthy?

Most fish deaths in a beginner's tank come from the water, not from disease.

Do

Treat all new water with a dechlorinator and match its temperature to the tank before adding it. RSPCA (England and Wales)
Rinse filter media gently in old tank water during a water change. RSPCA (England and Wales)
Change part of the water every week, with a gravel clean. RSPCA Australia Knowledgebase
Give fish a day and night cycle: constant light stresses fish and makes them more prone to disease. Merck Veterinary Manual
Choose fish that like the same water and get along, and use different levels of the tank. RSPCA (England and Wales)

Don’t

Wash filter media under the tap. The chlorine kills the helpful bacteria. RSPCA (England and Wales)
Add lots of fish at once. Add one or two at a time so the bacteria keep up. Merck Veterinary Manual
Buy from a shop with dead fish, cloudy water or crowded tanks. RSPCA (England and Wales)
Let fish be given away as prizes or sent by post. The RSPCA says posted fish suffer. RSPCA (England and Wales)
Release unwanted fish into a drain, pond, lake or river. Released suckermouth catfish from the aquarium trade now live wild in Kerala. Journal of Threatened Taxa (2015), Bijukumar and othersstudy

Are there any rules on keeping aquarium fish in India?

Rules for aquarium shops were notified in 2017 and then withdrawn, so the tank sizes in this guide come from welfare advice, not law.

In May 2017 the Centre notified the Prevention of Cruelty to Animals (Aquarium and Fish Tank Animals Shop) Rules, 2017, which would have barred shops from selling fish bowls and tanks under 60 litres and from placing tanks in direct sunlight. A news report of December 2017 said the notification was withdrawn on 30 November 2017. Those rules are not in force, but their thinking on bowls matches the welfare advice on this page.

Do not take fish, snails or plants from rivers, lakes or temple tanks for your aquarium, and never release aquarium fish into them. A study in Kerala found that suckermouth catfish, popular as tank cleaners, were introduced mainly through the pet trade, and that owners released them into drains when they outgrew their tanks. Such fish are likely to compete with native fish. If you cannot keep your fish, return it to a shop or pass it to another fishkeeper.

Going away needs planning too. A Petym sitter will visit on a schedule you set, feed the measured meals you leave, check the filter, heater and thermometer, and send a daily photo update. Petym is not taking bookings yet; it opens city by city once sitters have passed its checks. The cost of fishkeeping depends on the tank size, filter, heater, test kits, dechlorinator and food, the electricity to run equipment all day, a battery pump or inverter for power cuts, and care while you travel.

Going away soon? Tell us your dates.

A checked local sitter feeds, walks and keeps your pet company at home, follows your care sheet to the letter and sends a photo every day. Petym is opening city by city: send your dates and we will tell you when a sitter can take them.

Find a sitter to visit your home How it works

Meet your sitter first, free
PAN-checked, first-aid trained
A photo every day
Pay through Petym, never cash

Questions owners ask

Can a goldfish live in a bowl?: No. SPCA New Zealand says goldfish should never be kept in a bowl, and the RSPCA says bowls and jars were not designed with fish welfare in mind. Goldfish make a lot of waste and can grow large, so they need a big, filtered tank: SPCA New Zealand suggests 75 litres for one fancy goldfish.
How long should I wait before adding fish to a new tank?: At least two weeks, the RSPCA says, using fishless cycling, and the Merck Veterinary Manual says the helpful bacteria develop in 4 to 6 weeks. Add fish when ammonia and nitrite both test at zero, and add only one or two at a time so the filter keeps up.
Do I need to treat tap water for fish?: Yes. The Merck Veterinary Manual says most city water contains chlorine or chloramine, which are toxic to fish and to the bacteria in the filter. Add a water conditioner to every bucket of new water, or for chlorine, the RSPCA says water can be left standing for 24 hours.
How often should I clean a fish tank?: Change part of the water every week, about 10 to 25% in an established tank, with a gravel clean, using treated water at the same temperature. Rinse filter media gently in old tank water, never under the tap. Test the water every one to two weeks once the tank is established.
Can two betta fish live together?: Not two males. RSPCA Australia says two male Siamese fighting fish will fight to protect their territory and should never share a tank. A single betta can live with snails or large shrimp, and some small peaceful fish in a tank of at least 40 litres, but that is not for beginners.
Does a betta need a heater in India?: Usually yes. RSPCA Australia says a betta's water should be held at 24 to 26°C with a submersible heater, which only a tank, not a bowl, can hold. Check a digital thermometer every day.
What should I do for my fish in a power cut?: Put a battery-operated air pump in the tank, stop feeding until power returns, and keep the water cool by floating sealed bags of ice in summer. If the cut lasts more than five hours, a City of Riverside utility guide suggests changing about a quarter of the water.
Why are my fish gasping at the top of the tank?: Usually low oxygen, often in hot weather, after a power cut or in an overstocked tank. The University of Florida extension service says gasping at the surface is a sign of oxygen depletion that needs emergency aeration. Turn on an air pump, then test for ammonia and nitrite.

Keep reading

Getting a cat in India
Summer pet care in IndiaHeat waves and power cuts for every pet in the home.
What to leave for your pet sitter
Drop-in visits or overnight sitting?
Meet and greet checklist
Is it legal to keep a turtle in India?

Services that help

Free tools for this

Words on this page, explained

Keep exploring

More guides like this

Other care guides

Sources

Each source was opened and read on the date shown. How Petym checks its sources

RSPCA (England and Wales): Fish: caring for pet fish (opens in a new tab)checked 21 October 2026
SPCA New Zealand: Caring for goldfish (opens in a new tab)checked 21 October 2026
RSPCA Queensland: Siamese fighting fish (pet care blog) (opens in a new tab)checked 21 October 2026
Asthma and Allergy Foundation of America: Pet allergies: dog and cat allergies (opens in a new tab)checked 21 October 2026
Merck Veterinary Manual: Providing a home for fish (pet owner version, last updated April 2026) (opens in a new tab)checked 21 October 2026
RSPCA (England and Wales): Fish diet (opens in a new tab)checked 21 October 2026

Show all 17 sourcesShow fewer

RSPCA Australia Knowledgebase: How should I care for my Siamese fighting fish? (updated 1 May 2024) (opens in a new tab)checked 21 October 2026
RSPCA (England and Wales): Fish environment: tanks, filters, temperature and water (opens in a new tab)checked 21 October 2026
University of Florida IFAS Extension: FA27/FA002: Dissolved oxygen for fish production (Francis-Floyd and Pouder) (opens in a new tab)checked 21 October 2026
Riverside Public Utilities, City of Riverside (California): Tips for pets during outages: tips for aquariums (opens in a new tab)checked 21 October 2026
LegitQuest (legal database copy): Prevention of Cruelty to Animals (Aquarium and Fish Tank Animals Shop) Rules, 2017: text, rules 29 and 31 (opens in a new tab)checked 21 October 2026
RSPCA (England and Wales): Fish company: keeping fish together (opens in a new tab)checked 21 October 2026
RSPCA Australia Knowledgebase: Why is water quality important when setting up a fish aquarium? (opens in a new tab)checked 21 October 2026
Merck Veterinary Manual: Selection of fish (pet owner version, last updated September 2024) (opens in a new tab)checked 21 October 2026
RSPCA (England and Wales): Fish health and welfare (opens in a new tab)checked 21 October 2026
Journal of Threatened Taxa (2015), Bijukumar and others: Invasion of South American suckermouth armoured catfishes Pterygoplichthys spp. in Kerala, India: a case study (opens in a new tab)Peer-reviewed study · checked 21 October 2026
Orissa POST: Rights roll back (updated 4 December 2017): withdrawal of G.S.R. 493(E) of 23 May 2017 by a notification of 30 November 2017 (opens in a new tab)News report · checked 21 October 2026