The Best Guide for Starting a Reef Tank

Setting Up Your First Aquarium

If you want to start your very own reef tank, you’ve come to the right spot. Reef Builders will take you step by step on how to setup a reef tank from scratch. And, once you’re all set up, we have the information you need to keep your tank thriving. 

Who We Are

Reef Builders was established in 2006, and is the oldest running website providing news and helpful information regarding the saltwater aquatics industry. We have thousands of articles waiting to be explored and you can search for just about every aquarium topic by using our search bar in the top right-hand corner of the screen.

We’ve also organized our past articles by category making it easy for you to discover aquarium products, saltwater fish, corals, videos, and tips for keeping a successful reef aquarium. 



If you’re just getting started all of the information you find online can be overwhelming, so we want to make sure you have a place to refer back for all the basic. This Page features a step-by-step guide for setting up a saltwater aquarium, as well as useful links to past Reef Builders articles for when you are ready to move beyond set up.

We hate to break it to you, but there is no one size fits all answer for how to set up a reef tank. While there are components of the process such as equipment, husbandry, and maintenance which carry over, no two tanks, and no two aquarists are the same.

Some people may op to modify the order, frequency or speed of these steps, and aside from a few critical checks, this is absolutely fine. In fact, part of what we love so much about reef keeping is the diversity of aquarium displays and personal reef keeping methods. 

We’ve separated our guide into 6 steps. Within each step, we’ve broken down key topics and questions you may have. There are also links in each step if you would like more information on a certain topic. We hope you find this resource helpful for setting up your first aquarium.

Steps to setting up an aquarium 

Step 1. Planning

Step 2. Equipment and Set-up

Step 3. Saltwater and Water Testing

Step 4. Light, Flow, and Filtration

Step 5. Adding Fish and Corals

Step 6. Aquarium Maintenance


Step 1. Planning 


What to Keep

Before you get started it is best to have an idea in mind about what you want to keep in your aquarium. What first caught your eye and inspired you to start your own?  Knowing what you want to keep will help you decided which equipment you need before you make any purchases.

Most people just want to set up a nice looking aquarium with a good mix of fish and corals. This is called a community reef tank. Others may have a certain fish or coral in mind that they wish to keep. You may even want to keep an aquarium just for fish and skip the corals.

Whatever it may be you will want to do a bit of research before purchasing any equipment as different tanks have different care requirements.

Click here to learn more about choosing what to keep in your aquarium.

If you’re not picky, and just want to set up a nice looking tank, this guide will cover all the basic information you need to succeed.

Tank Size

Selecting your tank size is the second most important decision, after choosing what to keep. Tank size is determined by your budget, your livestock choices, and how much space you have to keep your new aquarium.

One of the secrets of reef keeping, bigger is always better.

Saltwater aquariums aren’t cheap, but there is always an affordable way to start keeping your own. Buying the biggest aquarium you can afford will pay off in the end by giving you a higher rate of success and more real estate to store your growing coral collection.

Bigger aquariums are also easier to keep because of what chemistry. There are several challenges with keeping an aquarium that pertains to water chemistry. We will cover that in more detail later but it is important to understand that changes in water chemistry happen slower in larger tanks because of there is more water. Bigger tanks are more forgiving.

Where To Keep Your Aquarium

It is important to select a place to keep your aquarium. You want to make sure to have enough room to work around the tank. You should keep your aquarium away from door or windows which have a cold draft and avoid placing your tank somewhere that receives direct sunlight.

When you know which size aquarium you will buy, search for the tank dimension online and measure out that space in your room. Make sure the tank, including a tank stand fits!

Read: Modern Aquarium Fish Room

Step 2. Equipment and Set-up

All-In-One or Build Your Own

All-in-one aquariums are a quick and easy way to get started in reef keeping. Build your own requires you purchase each piece of equipment separately and then learn to put it all together. Both get you where you’re going, and it just depends on how much you want to be involved in the process.

For beginners, the all-in-one is a straightforward way to go. All-in-one aquariums come in desktop sizes up to larger 140 G (525L) full-blown reef ready systems. 

Building your aquarium piece by piece is more time consuming, however, this option may save you a few bucks. If you have patience you can start building your aquarium with minimal equipment to get the saltwater flowing. Start by buying a tank and powerhead to create flow and build up your equipment from there.

Read More: All-In-One or Build Your Own.


If you’ve opted to build your own setup, here is the equipment you need to get started.

  1. Aquarium tank
  2. Aquarium stand (unless you have a desktop aquarium)
  3. Pumps
  4. Filtration
  5. Light
  6. Heater
  7. Saltwater
  8. Live Rock
  9. Sump
  10. Bucket or Plastic Container
  11. Rubber Hose or Tubing


Step 3. Saltwater and Water Testing


There are two ways you can get salt water. Either you buy it from a local fish store, or make your own at home. You will have to decide which method is best for you. For new aquarist or people with small tanks, purchasing water is a quick and easy way.

Local fish stores will sell refillable jugs around 5 gallons of water. Water is heavy so calculate how much water you need. Bringing home 50 gallons of water if you have to walk up stairs or make trips in an elevator may not be feasible.

Mixing Your Own Saltwater

Mixing saltwater at home is pretty straight forward. You make saltwater by mixing reverse osmosis de-ionized water (RODI), and aquarium salt, which you can purchase at a local fish store or online. Most aquarists keep large plastic drums in their homes for mixing saltwater.

There is no one size fits all solution here and any large Rubbermaid or similar storage container will do. Make sure you have a dedicated spot for your saltwater, and if you can make double or quadruple the amount of saltwater you need for a water change. It also good to have extra saltwater on hand in case of emergencies.

Read More: Water Changes

Water Testing

Water testing can be one of the more timely aspects of maintenance, but without testing, it’s difficult to know what’s going on inside your tank. Every time you test your water is a chance to correct any imbalances in water chemistry and improve the overall water quality of your system.

You should be testing your water at least once a week. Most local fish stores will help you test your water, however, aquarium test kits are relatively inexpensive and it’s a good idea to start testing your water at home. From the day you set up your aquarium until years down the road, testing your aquarium water should become an important aquarium ritual.

Read More: Water Testing and Aquarium Parameters

Water Parameters

Alkalinity- 8-12 dKH
Calcium- 350-450 ppm
Magnesium- 1250-1350 ppm
Phosphate- <0.2ppm
Temperature- 75 – 80°F (23.5 – 26.5°C)
Salinity- 35ppt or 1.0264 specific gravity

Step 4. Light, Flow, and Filtration


Proper lighting is important to the success of your reef tank. Corals are photosynthetic animals and need light to survive. That being said too much light too soon can cause unwanted algae blooms, and it’s always best to start out slow.

When purchasing a light for your saltwater aquarium it is important to buy a light which is built specifically for this purpose.

Lighting periods

When you first set up your aquarium, lights should be switched on for 6 – 8 hours per day. If you have a controllable LED light you can also reduce the light intensity. Once you’ve cycled your aquarium for six weeks or longer you can gradually increase the photo period. If you start noticing algae blooms decrease the intensity or length of daylight time.

Light zones

Depending on the size of your tank and rockscape you will create light zones in the aquarium with high and low lights. As in nature, different corals need different amounts of light.

Different light intensity zones are produced by the depth of the water and shadows created by the rocks. Light will be weaker at the edges of the tank and in the shadows of rocks. You can use a PAR meter to test light intensity.


Flow is an essential part of a healthy reef tank. Flow is created why powerheads and depending on the size of your reef tank you can one more than one powerhead creating flow. 

Water movement facilitates gas exchange and keeps your fish and corals healthy. 

Read: Gyre Flow




There are three types of filtration required for a saltwater aquarium Mechanical, Biological, and Chemical.

Mechanical filtration removed large particles from the water. Mechanical filtration is done by a sponge filter. This filter removes free-floating waste before it decays.

Biological filtration begins once your tank is properly cycled. Biological filtration is when bacteria in the tank breaks down dangerous ammonia, converting them to nitrites, and then the nitrites to less toxic nitrates. Biological filtration is also known as the nitrogen cycle.

Chemical filtration can be achieves using activated carbon. Activated carbon filter removes organic pollutants which cannot be removed by biological or mechanical filtration. 

Read: Mechanical


Step 5. Adding Fish and Corals

Adding Livestock

Once your aquarium has been running for six weeks or longer you can gradually add corals, invertebrates, and fish. It is important to start slow when adding livestock and we recommend starting with snails, hermit crabs, and peppermint shrimp.

When you are ready to add corals, start with hardy beginner corals like leathers, zoanthids, or mushrooms. These corals are perfect for filling up space in your aquarium and adding color.

When making your choice, you should remember that not all animals are compatible with each other. If there is one fish, in particular, you want to check their compatibility with other fish and work on that list.

Read: How To Fill Our Your Reef Tank When Getting Started

Step 6. Aquarium Maintenance

Water Change

Regular water changes are fundamental to maintaining an aquarium. The volume and frequency will fluctuate for each tank but almost every reefer performs regular water changes on their aquarium.

Water changes are a method to remove nutrients and replenish elements. A good baseline to begin your water changes is to change twenty percent of the water volume every week.

Read More: How to do a water change

Cleaning Protein Skimmer

Protein skimmers are most likely the dirtiest piece of equipment on your tank and is also the one you probably have to give it the most attention in order to keep it clean an operating effectively. 

Depending on the size and your bioload, cleaning your collection cup three times a week is a must to keep your tank smelling clean. If your water is fairly clean you may need to clean the cup only once or twice a week, but if you’re running a big bioload or are a heavy feeder, you may have to clean it daily.

Read More: Protein skimmer troubleshooting tips

Cleaning Aquarium Glass

We all want to preserve the clarity of our acrylic or glass aquarium. While sometimes it can be challenging especially with an acrylic tank, using the right tools will leave your aquarium clear of algae and scratch-free.

You will want to buy a magnetic scraper for weekly or daily cleaning. You will be able to clean the majority of the algae with a magnet. If you have an acrylic aquarium, make sure to use a magnet safe for acrylic. 

Read More: Tips for cleaning aquarium panels

Freshwater Top Off

When water evaporates from your saltwater aquarium, only the fresh water evaporates, and the salt is left behind. In order to maintain a consistent salinity level, we must top off our tanks with fresh water.

There are two ways to top off your tank, manually or automatically. Manual top off is simply adding reverse osmosis de-ionized water (RODI) to you tank, while automatic top off requires the use of a fresh water reservoir and auto top off device. There are several types of automatic top off systems but they all work to replenish your tank with fresh water.

Read More: How to top off your aquarium with freshwater

Helpful Reef Builders Articles

Using Trace Elements In Saltwater Aquariums

How To Feed A Reef Tank

Why It’s Important To Quarantine Your Fish And Corals

Asterina starfish, an introduction to this common reef aquarium critter

Palytoxin from Palythoa zoanthids is really, REALLY dangerous

An introduction to coral crabs, good and bad

What Is Salt Creep

How to Eliminate Aiptasia in Aquariums

Safeguarding Your Aquarium With Redundant Design

Aquarium Leaks, Floods, and How to Prevent Them

How To Remove Unwanted Fish From A Reef Tank

Traveling reefer blues and the anxieties of the vacationing aquarist

Tips to building a quieter reef tank

The Reefkeeper’s Skill Set

Common Coral Reef Pests and how to remove them