20-gallon tank setup: What fish and supplies do I need to get started?
Updated On September 23rd, 2025
I have a 20 gallon tank. I'm thinking of buying +5 fish. Which fish could I buy and what would I need for the fish and tank?
2 Answers
Most Helpful Answer
Published on November 23rd, 2017
A fish tank will need a filter, a light/hood and a heater. Make sure the filter is rated for at least twice the tank volume. The heater should be adjustable since water temperature will depend on the species of fish. Good "starter" fish include Tetras, Mollies, Danios or Tetras. A new tank should be set up and left running empty for several weeks before adding fish. A pinch of flake food can be sprinkled in daily. This "cycling" will allow a population of beneficial bacteria to colonize the tank and filter. These bacteria will break down wastes (ammonia, nitrites and nitrates) which are toxic to fish.
3Pet Parents found this answer helpful
Related Answers from Veterinarians
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Published on September 11th, 2017
At the very least, a 10 gallon tank with a filter, heater, hood and light. Ideally, the tank should be up and running (without fish) until it cycles properly. This means there needs to be sufficient time for beneficial bacteria to colonize the tank and filter to be able to break down wastes, namely ammonia and nitrites and to a lesser degree, nitrates. This can take several weeks to occur. You can cycle a tank with fish in it, but it will require daily testing of water chemistry to prevent a toxic build up of ammonia and/or nitrites. Either can kill your fish if not treated. Follow this link for a FAQ regarding Glo Fish: https://www.glofish.com/about/faq/ Follow this link for more about cycling a tank: http://www.firsttankguide.net/cycle.php
1Pet Parents found this answer helpful
Health & Wellbeing
I'm about to buy some new fishes mostly Tetra Can you help me what fish should I buy because I am beginner in this things. Please tell me what sort of things I should bring I have a one foot tank now other than that What should I purchase from Aquar
Before you buy any fish, you will need to set up the tank. A basic set up includes: a tank, filter, hood/light, heater, gravel and some decor. The tank should run without fish for at least 4 to 6 weeks. This gives it time to cycle. The Nitrogen Cycle is critical to the health of the tank and any fish you will be keeping. During this time, beneficial bacterial will populate the filter and substrate (gravel). These bacteria will be responsible for breaking down fish wastes and other wastes (uneaten food, dead plants, etc.). You will need a home test kit to monitor water chemistry (ammonia, nitrites, nitrates, pH) or you will have to submit water samples for testing. Most pet stores will do this for free or for a small fee. At first, you will see high levels of ammonia and nitrites. Over time, as bacteria grow, these levels will drop. When ammonia and nitrites are at 0 ppm and nitrates are below 20 ppm, you can consider adding fish. Regular (every 1 or 2 weeks) partial water changes as we
Updated on September 24th, 2025
Health & Wellbeing
I have 2 glo fish what kind of tank should I get?
At the very least, a 10 gallon tank with a filter, heater, hood and light. Ideally, the tank should be up and running (without fish) until it cycles properly. This means there needs to be sufficient time for beneficial bacteria to colonize the tank and filter to be able to break down wastes, namely ammonia and nitrites and to a lesser degree, nitrates. This can take several weeks to occur. You can cycle a tank with fish in it, but it will require daily testing of water chemistry to prevent a toxic build up of ammonia and/or nitrites. Either can kill your fish if not treated. Follow this link for a FAQ regarding Glo Fish: https://www.glofish.com/about/faq/ Follow this link for more about cycling a tank: http://www.firsttankguide.net/cycle.php
Updated on September 24th, 2025
Food & Nutrition
What types of fish should I buy because I'm a beginner in this . I have a 1 feet tank . One more thing I have heard that live-bearers could be best But I want your suggestion. And also what other Things I should buy and can you tell me a site that ca
Without anything to use for scale, it is hard for me to tell how big your tank is, but in general it seems very small. Also, the water that is in the tank appears very cloudy right now, so that would be the first place to start. Water quality is very important, and will make or break your ability to house and care for fish. I would recommend getting a good filter system (you can visit a local pet store to assist you with brands in your area, as I am not familiar with what you can get in India). Be sure to bring the measurements (height, length, width) of your tank, or the gallons or liters so they can tell you what capacity of filter you will need. Everything else will depend on what types of fish you get - if you plan on getting multiple fish, they will need to be small - a general rule of thumb is one square inch of fish per gallon of water. Depending on the species you get, you may need to also get a bubbler to ensure there is enough oxygen in the water for them, and you will also
Updated on September 24th, 2025
Health & Wellbeing
I'm doing a project for school about fish and here are some questions I have: What kind of fish is easiest to take care of? What size tank should someone start out with? What are some things people don't know about fish? What are the most common reas
Guppies or Neons are excellent "starter" fish. Care is simple and they are inexpensive. A standard 10 gallon tank is recommended to start. Most people don' t realize the amount of "work" needed to maintain a tank. Filter maintenance, monitoring water chemistry, water changes, monitoring fish health and providing a balanced diet are just a few items that need regular attention to keep a tank thriving. Even though fish aren't as cuddly as cats and dogs, they do have their own personalities and even respond to their owners, especially at feeding time! Studies have shown that simply watching fish in a tank can lead to a reduction in both heart rate and blood pressure. It is quite relaxing.
Updated on September 24th, 2025
Health & Wellbeing
setting up my first ever freshwater fish tank, need to know how many fish should I put in my 55 gallon fish tank,
For small bodied fish (tetras, minnows, guppies, etc) the general "one inch of fish per gallon" rule will likely be fine. For larger bodied fish (goldfish, plecos, Oscars, etc), it should be closer to one inch of fish per 3 gallons of water.
Always use the full grown adult size when deciding how many fish to keep. Take into account schooling fish as well which should be kept on groups of at least 5-6 fish.
Updated on September 24th, 2025
Health & Wellbeing
We have added fish to our newly set up aquarium twice now and both times the fish were dead or dying within 24 hours. The pH is at the proper level. The tank was filled with spring water. Why do our fish keep dying?
It is possible the tank has not cycled properly which results in high ammonia and nitrite levels which can kill fish.
Allow the tank to run, without fish, for at least 4-6 weeks. During this time, use a home test kit or submit a water sample for testing every few days. The local Petco may do this for free or for a small fee.
What you are looking for is to have ammonia and nitrites at 0 ppm and nitrates at 20ppm or less. pH can hover around 7 for most community fish. Avoid large, rapid swings in pH though. What is happening in the tank during this time is that beneficial bacteria are populating the gravel/substrate and the filter. These bacterial populations are responsible for the Nitrogen Cycle. This cycle breaks down wastes from fish, uneaten food and plant matter into by-products that are filtered out or dissipate. You can "cycle" a tank with fish, however this increases the risk of loss.
Once your tank has cycled, you can add fish. You will still need to monitor water chemistry a
Updated on September 24th, 2025
Health & Wellbeing
I am setting up a 20 gallon freshwater tank. I would like to have an assortment of live plants. I need recommendations on the type of plants to use and also the type gravel to use.
Our Standard Aquarium Plant Pack provides a convenient solution for your dilemma. This package includes Micro Sword or Dwarf Hairgrass, Anubias Nana or Anubias Barteri Round Leaf, Java Fern, Red Cryptocoryne or Green Cryptocoryne, Water Sprite, Hornwort, and Cabomba. http://www.liveaquaria.com/product/prod_display.cfm?c=768+2145+2146&pcatid=2146 A substrate specifically designed for live aquarium plants such as CaribSea Eco-Complete Plant Substrate is recommended for long-term success. http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=9087 Be sure to provide proper lighting conditions by employing aquarium light fixtures specifically designed for planted aquarium use.
Updated on September 24th, 2025
Health & Wellbeing
I would like to know how I can make my goldfish live the longest possible life they can and how to add more decor after I added the water and conditioning today and I am going to go get my fishies I think I am going to go with two but how to properly
Gold fish can make great fish but they can live up to 25 years and require a large tank that may need to be upgraded if they grow too large. Do get at least 2 fish. Here are some links which may help: https://www.petcoach.co/article/chewing-in-puppies-how-to-control-it/ https://www.aqueon.com/information/care-sheets/goldfish https://www.hartz.com/how-to-introduce-new-fish-into-your-aquarium-tank/ I hope this helps and congrats on your new pets!
Updated on September 24th, 2025
Health & Wellbeing
I got some new fish yesterday but I am not sure what type they are as they were s gift. They are black and a bit small. I want to know what type of fish they are and what they would need. Can you please help me with what type pf fish they are and wha
As for what kind of tank you will need: Basically a square fish tank, do not get a bowl. You will likely need a heater and an air pump, and a thermometer, It is easiest to by a complete kit at a pet shop. As for size of tank: The bigger is always the better....however a minimum size will be determined by the type of fish and their average size they will grow into, So once we know what type of fish you have and how many, we can tell you how big your tank needs to be and what type of "furniture" (rocks, plants, gravel) you will need.
Updated on September 24th, 2025
Health & Wellbeing
Can platties, Black mollies, pleco, and neon tetra all be kept together in a 20 gallon tank?
In general these fish can all be housed together safely. The one thing to keep in mind is the amount of space needed per fish to maintain a safe and healthy environment. Each 1in of fish needs 1 gallon of water. So in a 20 gallon tan you can have 20 inches of fish. The Pleco is the only one I have concerns with as some varieties can grow quite large. Check with your local pet shop as to what needs best suit this type of fish or what type of fish suit your tank best.
Updated on September 24th, 2025
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