Starting a fish tank is fun for people of all ages.  However, fish keeping involves a learning curve more complex than most people think.  While it is not that hard to learn about fish keeping, it is recommended to learn the basic knowledge before buying fish.  Or the pet fish you buy will most likely end up dead.  Millions of aquarium fish die every year in home aquariums.  Most of them do not live longer than a few weeks.  We can easily avoid such tragedy if everyone has learned what to do before getting started.

A newly set up fish tank

The following are some important things everyone must know before starting a fish tank.

1.  Fish keeping is fun and addictive

For obvious reasons, it is fun to have one or more home aquariums.  Once you sort out all the newbie problems, you will find a whole new world in front of you.  As time goes by, you might discover new species of fish you want to have.  Or new kind of aquarium setups you like after saw it in a picture or video.  Or perhaps you want to try to have your fish reproduce and watch the fry grow.  Eventually, you will need more than just one fish tank. 

I remember one guy said in a fish video:  Before you know it, you have more tanks than friends. 

It is so true.  During the first year of my fish keeping, I went from just one fish tank to total four.  

So yeah, keep in mind that once you successfully get into the world of aquarium fish keeping, it will become more and more fun and addictive.  However, the key is to get past the newbie phase, which requires a learning curve. 

2. Fish will die if you do not know what you are doing

A lot of people would go to a pet shop and bring home the fish on the very first day.  In many cases, some people might even just suddenly decide to buy some fish when they see them in a shop.

I know the temptation of getting fish when you see all the beautify fish swimming in the tanks at a shop.  In some cases, your kids might bug you to buy for them.  If you do not already have established fish tanks at home with some experiences, you must avoid getting fish before getting to know the basics.  Without a proper planning, everything is set to fail. 

The very first thing you must know is NOT to bring some fish home just like that.  Fish keeping requires specific knowledge (easy to learn, but you still must know them first).  Most fish die within a few weeks after people brought them home due to all kinds of newbie errors.  If you do not want to end up with the waste of time, money, effort, and a saddened heart, please be a responsible fish keeper and do your research first.  

There is a long list of things you must know before you buy anything at all for a home aquarium.  You may use Google, or any other search engines, to find fish beginner type of articles. 

Examples of important topics to know:

How to set up a home aquarium; 

As well as research on individual aquarium equipment and supplies such as:

fish tank size;

aquarium filter;

aquarium heater;

air pump;

aquarium water conditioner;

fish food,

etc. 

If you still have questions after read all the articles, you may use online fish forums to ask questions.  There are always many experienced fish keepers who are happy to help you out. 

3. Fish keeping requires your full commitment

Like owning most pets, fish keeping will cost money, time, patience, and some physical work.  While the need of overall commitment is quite low in fish keeping compared to owning some other pets (at least you do not need to walk your fish or get vaccines for them), it requires more than half-assed effort to make both you and your fish happy. 

The commitment of fish keeping includes but not limits to the time spend on doing research and planning, the initial setup cost, the cost of the fish, maintenance/upkeep cost, as well as the physical works to set the aquarium up.  There is also weekly maintenance which requires your time and energy to keep the aquarium in good condition.  If you can’t afford it or unwilling to spend the time, money, and energy, it is a good idea not to get fish as pets.   If you are up for the challenge, go for it and you will enjoy it a lot once you get the hang of it.  

4. The cost of starting a fish tank can be expensive

While starting a fish tank might be a lot cheaper than keeping a dog or cat, the real cost (if you do things properly) might be a lot higher than you might think.  It is more than just buying a fish tank and a few fish. 

A 10-gallon glass fish tank might only cost $14~15, and most small tropical fish only cost $1~3.  But you can’t get away with just spending money on a fish tank and a few fish.  They will die if those are the only things you buy. 

At the very least, to start a fish tank you will also have to buy an aquarium filter, aquarium water conditioner, and fish food on the top of the already mentioned fish tank and fish.  They are mandatory.  If your fish is tropical (most aquarium fish are in fact tropical), having an aquarium heater is also a must unless you live in a tropical area.  An aquarium air pump is required in most circumstances since we need to ensure the water has enough dissolved oxygen for the fish to breath.  You will also need air tubing and airstone to work with the air pump.  

Other things like gravel, decoration, a canopy, lights, thermometer, are also good to have if you truly want to enjoy your aquarium. Maintenance tools such as gravel vacuum, algae scraper, fish net, water bucket are also nice to have if you want everything to go smoothly.  The cost quickly adds up.  At the very least, you will need to prepare around $100 USD for a small, basic setup of 5~10-gallon.  

Larger aquariums will cost more.  For example, a 90-gallon fish tank can cost anywhere from $500 to $700.  For such heavy fish tank, you will need a dedicated aquarium stand.  Bigger fish tank requires everything bigger.  It means, bigger aquarium filter, bigger aquarium heater, bigger canopy, bigger lights, more gravel and decorations, bigger bottle of water conditioner, etc. A full setup of a 90-gallon fish tank with everything new will cost you more than $1,000 for the initial setup. 

There are fish tanks of 120-gallon, 150-gallon, and even 300-gallon or above.  It can cost you thousands of dollars to set up one of those 300-gallon fish tanks once everything is set.

Then there is the water and electricity bill.  Depends on the fish tank size, it could cost anywhere from $3~30 or more per month as a part of the upkeep.

Some people might think they can save money by getting smaller fish tanks.  I would advise against it.  The minimum fish tank size requires to keep the water conditions stable is a 5-gallon.   Since a 5-gallon fish tank is usually only $2 cheaper than a 10-gallon tank ($12~13 vs. $14~15) at most places, might as well get a 10-gallon as a starter tank.  It will give you more options in the long run.  You can have a few more fish, and maybe slightly bigger fish in a 10-gallon than a 5-gallon. 

For a more detailed list of aquarium equipment and supplies you need to start a proper setup, please refer to the article of essential and nonessential fish aquarium equipment and supplies. 

5. Fish keeping requires space and an ideal placement

The location to set up a fish tank is quite important.  A fish tank takes space.  Make sure your home has the available space for the fish tank and the aquarium stand.  More importantly, you will need a good spot to place it as its location is relatively permanent.  You need extra consideration and planning if you live in a small apartment since some locations are not good for a home aquarium. 

6. You need to cycle a new aquarium before getting the fish

Aquarium Nitrogen Cycle is the backbone of the fish keeping knowledge.  Everyone must pay extra attention.  Fish produce ammonia on a constant basis which is toxic to the fish themselves.  In a closed system such as a home aquarium, the ammonia will build up and kill the fish.  No amount of water change will solve the problem permanently since the ammonia is produced every second on a constant basis.  It will build up between water changes. 

The permanent solution is to relay on the aquarium nitrogen cycle.  The term aquarium nitrogen cycle refers to the process of the toxic ammonia being converted to less harmful form by naturally occurring bacteria in the fish tank.  Most of these good bacteria will colonize surface areas of objects only.  The one thing in the fish tank with the most surface area is the filter media.  It is why the aquarium filter system is so important.  

In a new fish tank, there is near zero beneficial bacteria.  It takes many weeks to several months to build them up to sufficient number.  Before we achieve it, the fish tank is off-limits to the fish.  Unless you want them to die of ammonia poison.  So the first thing you need to do after starting a fish tank is to do a fishless cycling.  

7. Fish acclimation is critical when getting new fish

Fish are more fragile than humans, and they are prone to shock (and die) in unstable water conditions. 

A lot of people complain why they fish died shortly after put them into a fish tank.  In most cases when the fish died within a day or two, or even in hours, it is due to shock.  Any large, and sudden change in water temperature, PH, hardness, can shock and even kill the fish.  Die to shock contributes to the quickest deaths in fish keeping for beginners. 

To avoid fish deaths to shock, we must acclimate the fish.  Give them time to slowly adapt to the new water.  

8. Not all fish are compatible

Some fish such as goldfish are cold water fish.  While most other fish in the aquarium trade are tropical.   You can’t put them in the same fish tank.   The tropical fish need a heater, while goldfish does not. 

Some fish species are aggressive toward each other.  You might not want to put more than just one in the same tank. 

There are too many examples.  It all comes down to what species of fish you want, and do some research on each species. 

9. Overfeeding is a big NO NO

Overfeeding will directly kill the fish through digestive problems.  It can also kill the fish indirectly through water pollution.  Even if none of the above happens, it might still contribute to an algae bloom and a dirty fish tank.  It can end up cost you more maintenance time.  Never overfeed your fish if you want the best for your fish and yourself. 

10. Fish keeping require constant maintenance

Even if your aquarium is healthy and beautiful, with all the fish happily living in there.  It won’t last unless you do regular maintenance.  Weekly partial water change along with gravel vacuuming is required to keep the fish healthy, and the aquarium clean.  If you have a planted aquarium with live plants, the upkeeping is even more time-consuming.  I have experienced just that.  Aquatic plants do not stay in top conditions.  Often time they will overgrow and require trimming from time to time.  Sometimes they will have algae growing on their leaves which can kill them by blocking the light.  You have to manually clean them or simply remove some parts of them. 

In any case, fish keeping is not something you can just set it up and enjoy it for the rest of the life without doing some work for it from time to time. 

Conclusion: 

Fish keeping is one of the most fun hobbies in the world.  There is no question about it.  It can also be frustrating to the newbies who are not correctly guided by the right information.  The ten things mentioned above are not the only things you need to know.  As you get deeper into them one by one, you will discover more topics by yourself.  Knowledge is power.  Please learn the basics before you starting a fish tank.  Read up the relevant articles, and ask questions on the fish forums before buying fish.