How to Set Up a New Fish Tank

6 min readJul 17, 2023

Starting a brand new aquarium can be an exciting time for anyone, but there can be an overwhelming amount of information out too. Wouldn’t it be nice if someone with more than 25 years of aquarium-keeping experience could come in and walk you through the whole process? Well, here I am, so let’s get started!

How Much Does It Cost to Set up a Fish Tank?

This can be a question that varies greatly. While some aquarium fish at your local pet store might only have $2 price tags, properly setting up their home with everything they need can cost $200 or more.

Fish Tank Shopping List

Aquarium

Large chain pet stores in the US such as Petco, will have “dollar-per-gallon” sales on a lot of their aquariums. You may be able to wait until one of these sales and purchase a 29 gallon aquarium for less than $30. Walmart often sells 10 gallon aquariums for $15, and has complete kits with a lighted lid and some other accessories for $30.

Complete beginners to the aquarium hobby will probably start with a 10 gallon tank, and this is perfectly fine. However, many hobbyists agree it’s better to start with a larger tank even if you are brand new to the hobby. 29 gallons or even a 55 gallon tank, if you have the room for it, can offer long-term water stability and won’t be as prone to ammonia buildup or other issues.

Keep in mind that 1 gallon of water can weigh 8 pounds by itself, so a 10 gallon tank will weigh at least 80 pounds. This doesn’t include the weight of the aquarium, substrate, decorations, filter, and lighting! Make sure the place you plan on putting your aquarium is fully able to support this immense amount of weight.

Heater

While there are plenty of fish that can live happy lives in unheated water, such as ricefish, mountain minnows, and goldfish, most other freshwater fish will need tropical water in the 75–80°F range.

Heaters can be found in various wattages which can be confusing to understand. As a base line, 5 watts on your heater is good for 1 gallon of aquarium water. If you have a 5 gallon desktop aquarium for a betta fish, consider getting a 25 watt heater.

Filter

Many people will say you should jump right in and purchase a canister filter as your filtration option. And while canister filters can be excellent filtration, especially for larger tanks, they are also extremely expensive, can be difficult to set up, and even more difficult to clean and maintain.

For your first filter, look for a filter that hangs on the back of your aquarium. These are the “entry-level” aquarium filters, but can perform their job perfectly fine. These filters are affordable, easy to set up, and very easy to maintain.

You can also consider using a sponge filter, which is my personal choice for aquariums of almost all sizes. With the exception of my largest tanks, most of my 175 gallon or less aquariums use sponge filters with excellent results.

Lighting

If you purchase an aquarium starter kit in a box, chances are it will already have a lid with a light. This light is perfectly fine for fish, but if you plan on growing aquarium plants you may need to invest in a higher quality LED light.

Keep in mind, the brighter your lighting, the more algae issues you may run into. While some algae is perfectly fine to keep on your aquarium walls and decorations, because fish, snails, and shrimp like to munch on it, it can look unsightly and may give your aquarium the illusion of being dirty even if it isn’t!

Substrate and Decorations

Substrate is the gravel or sand you have as the flooring of your aquarium, and there are dozens of choices for this. Gravel can come in a wide range of colors from neon pink to natural tan. I personally prefer natural colors, but other people prefer solid black or even bright neon colors for their children’s bedrooms.

Whatever your color choice, always be sure to thoroughly rinse your sand or gravel with clean water before adding it to your tank. Don’t use soap or any kind of cleaning products since this can be dangerous to your fish. Instead, just let fresh water run through the gravel or sand as you move it around with your hand. This will remove the dust and unwanted debris before you add it to the tank.

Decorations can include caves, floating plastic lily pads, or leaves that suction cup to the side of the glass. Background images can also be considered a decoration and will help hide the electric cords and other cables that come with your lighting, heating, and filtration.

Other Accessories

Water conditioners are an important product to keep on hand, especially if you live in an area where your tap water is treated with chloramine or other chemicals. When you fill-up your tank with tap water, be sure to add aquarium water conditioner as per the instructions on the bottle.

An aquarium siphon is also a must-have accessory for your fish-keeping endeavor. This not only helps make draining and refilling the tank easier, but it can also help keep your sand or gravel substrate free from uneaten food, poop, and other messes.

How Long Before You Can Put Fish in a New Tank?

You might be reading this question and wondering what in the world I’m talking about. “But Sierra, can’t I just buy an aquarium, fill it with water, and plop a bunch of fish in?” Well, yes… but you might not be able to enjoy those fish very long before they start dying. And nobody wants that!

Adding fish to a brand new aquarium can take time, and this is the step where a lot of people lose interest and give up on the hobby entirely. But, if you can wait two weeks or even longer before adding fish, it will be well worth it in the end!

Your tank needs time to set up and get established with beneficial bacteria. This can take two weeks, or it can take six weeks. By not rushing the process, you ensure that any fish you decide to add to your aquarium will lead long and healthy lives, free from stress, or disease along the way.

Setting Up The Tank: Step by Step

Decide where to put your aquarium
Rinse out the aquarium and all of the substrate, decor, and accessories
Place the aquarium in its new spot
Add the substrate and decorations to the aquarium
Place the heater in the aquarium and stick it to the glass with the suction cups
Fill the aquarium with water from the tap
Add your water conditioner or de-chlorinator
Place your live aquarium plants, or finish adding your floating decor
Put the lid on, but wait 30 minutes before turning the light on
After 30 minutes, turn the heater and filter on
Check back in 24 hours for any leaks or issues with the decorations
Start cycling your tank and getting beneficial bacteria to grow
After two weeks of cycling, check your water parameters
If they are stable, add 1–3 fish and monitor their behavior
Keep checking your water parameters each day
If ammonia is not spiking and everything looks good, add more fish if necessary
Enjoy your fish-keeping experience!