Setting Up a Reef Tank – Complete Guide

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Are you looking to have a piece of ocean life in your home? Then the closes thing to the ocean life you can recreate it with a saltwater reef tank. A reef tank is a saltwater aquarium where there is plenty of corals and saltwater fish that will make the aquarium look just like a coral reef in the sea.

Prior to composing such a reef tank, you need to make some research about the species and how they live in the wilderness and how they get along with other fish.

Some fish might be predators, while other fish might often be hunted, which is why they seek shelter and often hide behind the reefs and the environment. You need to create such an environment where the fish will co-exist in symbiosis and will not obstruct each other.

A reef tank is usually consisted of only fish and live rock and the whole system requires a higher quality lighting and filtration system. Be prepared to spend a little more on the lighting to keep the little tank inhabitants happy.

All this can be an intimidating prospect for a beginner. If you have never owned an aquarium, let alone a reef one, then this article is perfect for you. In this article, I will provide you with the complete guide of how to set up a reef tank and fill it up properly – which tank to use, which fish go together well, and I will cover every other little detail that you need to know when setting up a reef tank.

If you are planning to start with small reef tank, please consider reading my linked article to find out which are the best fish for nano reef tanks.

So without further ado, let’s get started with the guide. First, we will take a look at the right aquarium size for your needs.

Choosing Aquarium Size

Choosing Saltwater Aquarium Size

Choosing Saltwater Aquarium Size

The first thing you will need to worry about is picking the right aquarium size. This, of course, depends on your personal preferences.

But if you have never owned an aquarium and you don’t know too much about reef tanks, I recommend that you get at least a 30-gallon tank up to 55-gallon tank.

Why is that, you might ask yourself? Well, firstly it is because larger tanks give you more freedom and allow you not to overstock the population, which can easily happen if you have a small tank (10-gallon to 30-gallon), and that often happens for beginners.

They tend to disregard the size and how much space a fish species might use. This is why they put too many in a small space and the fish struggle to get their living space in order to thrive.

Choosing a 30-gallon tank or more will help you remedy that – you will have more space to put the fish you want to keep.

Additionally, smaller reef tanks tend to be a little bit more complicated in terms of water chemistry and getting it right, because you have to be more precise due to smaller amounts of water.

So smaller tanks, contrary to popular belief, tend to be a bit more complicated and require a bit more maintenance than larger ones.

For these reasons, I recommend you get a 30-gallon tank to a 55-gallon tank if you are new to the aquarium business.

Aquarium Filter

The next thing on your mind after purchasing the aquarium should be getting the right aquarium filter for your tank size. This is a very important aspect of setting up a tank that will be functional from the very beginning.

Water filtration is often overlooked and disregarded but is actually one of the most important things with new aquariums.

You want to keep your water as fresh and as clean as possible so that the fish will remain happy and healthy. This will promote longevity with the fish and a healthier environment overall, but also it will prevent you from spending more time with maintenance and cleaning the water itself.

Usually picking a stronger filtration will go a long way with water quality and cleaner water overall, which will reduce the costs and time consumption in the long term.

If you choose a 30-gallon to 55-gallon tank, then this filter is your recommendation.

The Fluval external filter is a great universal and very versatile choice as a filter for your aquarium. It has multi-stage filtration and is suitable for aquariums of up to 100 gallons.

So it is actually a bit stronger than your aquarium requires it to be, but this will help in the long-term to keep it cleaner.

Consider the Fluval external filter as a versatile filtration choice for your new reef tank.

Saltwater Filter Media

When setting up a filtration system, there are more phases of filtration you need to keep in mind. The most effective filtration system uses three different media for filtration.

Let us take a look at each one of them and what they do. We have mechanical, chemical and biological media, and all of them are required to work together efficiently.

Firstly, there is the mechanical media filtration, which is the first phase in the filtration process. In this stage, the filtration system clears the water of larger and visible pieces of debris.

This can be uneaten food, pieces of leaves or just other debris that accumulates through time. Mechanical media is a dense mesh or even ceramic rings that form a barrier in your filter. This keeps the debris out of the water and keeps the flow going,

Next, there is the chemical media phase in your filtration, which removes the invisible things from the water, the chemicals you cannot see, like ammonia.

This is an important phase where you will get rid of the unwanted chemicals in your water. The most common chemical media for filtration are carbon and zeolite.

Lastly, there are the biological media which makes sure that there are enough beneficial bacteria in your saltwater.

This does not mean that you will add beneficial bacteria right into the water, but it actually means that you will provide them with the right conditions to thrive in your tank, and this is achieved by the biological media with the biorings or even ceramic rings.

Aquarium Lights

The next step in setting up your aquarium is to set up the lighting system of your tank. I talked about the importance of this step already above, and it is essential that you provide the right lighting to your tank that will keep the fish happy and will recreate the conditions of the real-life saltwater areas.

This part is, again, going to depend somewhat on your personal preferences for the lighting. But as I said already, you do not want to be saving money on some cheap lighting system that will be inadequate for your tank.

You want to provide a high-quality filtration system and then lighting system – these two steps together are arguably two of the most important things for your tank.

Take a look at this LED lighting system by Phlizon available on Amazon . It is a 165 W full-spectrum lighting system that will provide your fish with the best possible lighting system.

It features a unique design that will ensure that it will provide a high-quality lighting system and you do not want to be saving money on this part. Instead, make sure that you provide the best possible lighting for your tank.

Protein Skimmer

Besides a good filtration system with a good biological media, providing your aquarium with a protein skimmer can be actually quite an important part of cleaning your water.

Protein skimming, or also known as foam fractionating. In essence, protein skimmers provide the saltwater with bubbles, where some undesirable ingredients collect and can then be eliminated from the water.

These bubbles might not be visible by our eyes, but the protein skimmer will blow these bubbles. These air bubbles are shown to increase the water quality significantly in water treatment plants before, so there is no reason why you should not use it in your reef tank as well.

The skimmer will help you get rid of the compounds in the water that produce a yellowing effect, such as dissolved organic compounds and phenol oils. These compounds are harmful to the quality of the water and the skimmers will get rid of them to prevent the water from yellowing and keeping it as fresh as possible.

This protein skimmer is a good choice for your aquarium system.

The Aquatic Life’s 115 mini skimmers should be more than enough for your tank size and are even suitable for larger tanks. Consider a protein skimmer to keep your water as clean as possible and to get rid of some of the harmful chemicals that can significantly lessen the quality of the water.

Water Heater

An important part of a good set up for a tank is also taking care of the proper heating for the fish. Making sure that the water has the right temperature is essential to keeping the fish as healthy and as happy as possible.

This is why you need to perform temperature checks on a daily basis and you have to know how your fish prefer to live – in what sort of water temperature they thrive.

If you keep your tank in a cold area where there is little or no sunlight, then getting a water heater might be an important step for you.

Also take care that the water is not too hot, because that can hurt the fish in the long-term as well. So keeping it in the right area is the best thing you can do.

This water heater above is an affordable option but it does not compromise on the quality of the product. The Eheim Jager thermostat heater is a quality product that will help you keep the water temperature at optimal levels. This is a dipping tool that will also automatically turn off if the water levels are too low.

It is a very resistant and durable water heater that can be used for almost every tank size, so consider this water heater source for your reef tank.

Wave Makers

If you want to make your fish friends extra comfortable, then you might want to buy a wave maker to make them feel right at home.

Wavemakers are a good option to recreate a feeling of being in the sea for the fish, and it will help them acclimatize to your aquarium much easier and quicker. This is why I recommend you getting a wavemaker as well.

There are more types of wavemakers – some are more powerful, while others are subtle and produce just a slight amount of power to create waves in your tank. Which one you will choose will depend entirely on your own personal preferences and also the fish you have in your tank.

Some fish prefer rocky and wavy waters, while others prefer to leave in more peaceful conditions. Ideally, you want to keep it somewhere in between and in moderation. This below is my recommendation for a wavemaker.

Hydor Koralia is a good option for a wavemaker and is an affordable option for you to produce the waves that your fish will just love. It uses different strengths to produce various amounts of waves in your tank, from stronger waves to more peaceful and subtle waves. You can adjust it to your needs.

Choosing a Substrate

Another important choice for your tank is choosing the right substrate that you will use in your tank. Choosing the substrate will obviously depend on the fish you want to have in your tank and also on which substrate you think is perfect for your tank and your needs.

Generally, some crushed corals will make a good substrate for your reef tank as it will recreate the conditions of the coral reef accurately and the fish will feel right at home.

As for how much substrate to use, it depends on how many fish you will keep and what sort of fish you intend to keep. If the fish like to swim in and around the substrate, then a thicker layer is the way to go. If you have more lively fish that like to swim around a lot, then put a bit less substrate, and you can always add more of it later.

Also, you mustn’t ignore the importance of keeping the substrate as clean as possible. This is why you will need to clean it regularly – ideally once or twice a week – to keep it clean.

There might be a lot of debris and dirt collecting in between the substrate pieces, so vacuuming the substrate from time to time to clean it would be a good option you should consider.

As for substrate recommendations, I recommend that you check out this substrate in the link below.

This is the Carib sea substrate available on Amazon, that is consisted of crushed corals, and it would be perfect for a reef tank that will do the job for you perfectly.

Choosing a Salt mix

What is a salt mix, you might ask? It is a mixture of ingredients that you should put into the water to make it more appropriate for a reef tank and make it closely resemble the saltwater conditions.

The salt mix should contain some important ingredients. The three most important ingredients that should be in the salt mix are calcium, alkalinity ingredients, and magnesium. Also, some minerals should be in that mix.

Calcium is a very important ingredient in a reef tank. It allows the corals to build their stony skeletons and to develop their shells correctly. Without it, these skeletons would not be as strong as they would be with them.

You should not save on the salt mix, as it would be a shame if the corals would not get enough calcium to develop properly.

Secondly, you need to consider the alkalinity of the mix itself. The saltwater is considered to be more alkaline, so it is essential that there are enough alkaline elements in the water. You need to keep the alkalinity of your water in check at all times, though.

This is a good choice for you.

Adding Live Rock

Live rocks are not just decoration pieces in your water tank, but they also play a role in some other areas, such as helping the fish settle easier in your tank and also providing some minerals to the water. This live rock would be a good choice for your reef tank.

This is an aragonite natural rock with natural holes and it provides a great natural decor piece as well as providing some natural filtration and it denitrifies your water – it gets rid of the nitrates in the water and thus making the water more appropriate for the fish.

Cycling Your Reef Tank

This is a very important part of keeping a tank clean. You want to perform maintenance checks on a regular basis, and cycling the water regularly should be at the top of that list. Doing this will help you clean the water better and easier, but also it will prevent some of the harmful bacteria from developing in the water.

Despite having a strong and effective filtration system, making sure that you cycle the water frequently and properly on a regular basis is an important step to making sure that the water is clean at all times. The fish will produce debris and waste regularly, and with cycling you can get rid of that. You will get rid of ammonia, nitrites, and nitrates in this way.

Firstly, you want to test the water regularly with test kits. We will discuss this later on. Cycling the water can take up to a few weeks, so you will need to be patients. Next, add the 100% pure ammonia in the water and in the amounts that are prescribed on the ammonia packaging.

The ammonia will then be converted into nitrites by the bacteria, which is still toxic for the fish. The last stage of cycling is the conversion of the nitrites into nitrate. Which is a non-toxic ingredient and is the last stage of cycling.

It is an important part of keeping the water clean and appropriate for the fish to live in it.

Saltwater Aquarium Test Kits

In order to know if your water is at the optimal levels, you will need to test it often. This way you will know if your water needs cycling or if it needs to be warmer or if it is too cold. For this, you will need aquarium test kits. These kits will over time become your friends that will let you know if you are keeping the water at optimal levels.

I have two recommendations for test kits in this article. The first recommendation is a salinity refractometer with automatic temperature compensation – click here to buy it from Amazon.

This kit measures saltwater and the salinity of the water and it features automatic temperature compensation. It is a good test kit for your reef kit.

My other recommendation is the Salifert Master Reef Testing combo kit, which is also available on Amazon. This kit is the complete kit for your aquarium. It contains all the important tests that you need to conduct. It contains the calcium, nitrate, phosphate, ph, alkalinity and magnesium tests.

Consider these two test kits when you start your tank to measure the levels of chemicals and salt in your water to keep it at optimal levels for the fish.

Adding Livestock and Coral

Adding Livestock and Coral

Adding Livestock and Coral

One of the last tasks, but also one of the more exciting ones, are choosing the livestock and the coral for your tank. Now, this is a subjective choice. You can choose whatever fish and the coral types you want in your tank.

You do need to make some research prior to doing so, though. And you want to make sure that the fish you get in your tank are compatible with each other and that they get along well. Which means they have to be friendly and peaceful.

Make some research about the character of your fish you are trying to get into your tank. How it behaves and how much attention and time it requires, because if you are not willing to spend that time for maintenance and for keeping the fish, then it might go very wrong.

As for the corals and other decorations, this is a subjective choice and you will be able to pick the one that you like the most. Just make sure that it is not too big for your tank as that will massively decrease the space for your fish and they will not be so happy in that environment.

Also, do not overstock your aquarium. With tank sizes of 30 – 55 gallons you should be fine. But if you put too many fish species in it might become a mess and the fish would not have enough space. So make sure that you give your fish enough space to live.

Do you Need a Quarantine Tank?

What is a quarantine tank? It is basically an additional tank that you can have besides your main tank where you can keep your ill fish or new fish for some time to acclimate.

You can also keep the fish in the quarantine tank prior to putting them into the main tank to acclimatize to new conditions and make the transition easier.

Having a quarantine tank depends on you. But I would recommend having one as it is not too expensive. It doesn’t need much maintenance and is quite easy to set up.

All you need is a tub to use as a tank, a small heater, a small filter, and a pump and a small piece of hiding place for the fish. It does not require much and it can be very useful to have a quarantine tank.

Can You Use Tap Water for a Reef Tank?

No, you cannot use tap water for a reef tank, because it contains some chemicals like chlorine that will harm the fish.

These chemicals are used to make the water usable and drinkable for humans, but for the fish it can be harmful.

Also, tap water does not contain the salt, the minerals and the chemicals that a reef tank should have, so you need to prepare the water first.

You can only use RO/DI water mixed with salt for the reef tank. For making RO water, I recommend this product from Amazon.

How to Maintain Your Saltwater Aquarium?

You need to perform regular maintenance checks with test kits. Check the temperature and clean the water regularly and cycle it. Also, feed the fish quality foods and don’t compromise on the quality.

Best Saltwater Aquarium Kit

If you want the simplicity of having everything pre-arranged, then get an aquarium kit. I highly recommend the Fluval Evo XII. This kit comes with a 13.5 gallon aquarium. And includes all the necessary equipment you need to start a reef tank.

This tank has an in-build compartiment, which houses the aquarium heater, the skimmer and the filtration. Filter media is included. The filter is oversized in order to provide a better 3 stage filtration: mechanical, biological and chemical. The filter is silent but very efficient

The aquarium kit also has a lid, which prevent water evaporation and fish from jumping out. The lid houses the the LED lights, which are 14000 K, perfect for growing corals.

If you choose such a small aquarium for salt water, make sure you research really well what type and how many fish you can add. There are some saltwater fish that will be fine in such a tight space, but most fish need larger tanks. So please consider this factor too.


I hope you learned a lot about how to set up and maintain a proper reef tank in this article. Good luck and have fun with your new reef tank!

If you have any question regarding this topic, please leave a comment below and I will try to answer as soon as possible.

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.

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