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  • Writer's pictureStewart Kessel

10 Easy Steps to Setting up an Aquarium

Updated: Jan 8

Step-by-Step Guide and How to Avoid Costly Mistakes

Are you thinking of setting up your first freshwater aquarium, but maybe confused about how to start? Well, the good news is that as long as you follow ten easy steps, it is simpler than you may think.

We will list out the ten steps for you to follow. It pays to take your time at each stage, ensuring you get everything right and thereby avoiding costly mistakes. Most beginners fail due to poor advice or taking ill-advised short cuts to save time. 

Owning a freshwater aquarium and keeping fish has many benefits. Not only do they bring a slice of nature into the home, but scientific studies have shown that they can have a positive effect on physical & mental wellbeing, helping reduce stress & anxiety. They are also a great learning opportunity for children. So, let us help you achieve your dream freshwater aquarium. 

In our article ‘What do I need for my First Aquarium’, we discussed the essential items required for the set-up of your first fish tank. As a reminder here is the list of those items, but I would strongly suggest it is worth revisiting the article for more detailed information.

· Aquarium & Cabinet (optional)

· Filter

· Heater/Thermostat

· Thermometer

· Lighting

· Substrate

· Aquarium Décor

· Water Conditioner (de-chlorinator)

· Source of Ammonia

· Aquarium Water Test Kit

· Fish Net

· Water Syphon/Gravel Cleaner

· Bucket

This article provides a simple ten-step guide to setting up your first aquarium. Including an explanation of the necessary process at each stage and if required links to other more specific detailed information to guide you on your way.

10 Easy Steps to Setting up a Freshwater Aquarium

Step 1 Research & Planning

Step 2 Choosing a Location

Step 3 Set Up Aquarium & Cabinet

Step 4 Add Substrate

Step 5 Decorate - Hardscape

Step 6 Install Equipment

Step 7 Add Plants [Optional]

Step 8 Treat and Add Water

Step 9 Cycle Aquarium

Step 10 Add Fish

Step 1 Research & Planning

Researching and planning are essential to determine what type of aquarium set-up and hence fish that you want to keep. Not only will this dictate the required size of the aquarium, but also what water chemistry, temperature and the habitat required for your chosen fish species.

Consider whether it is cold water, temperate, or tropical freshwater aquarium that you desire. Are you going to keep compatible species of fish with similar water requirements together in a community aquarium, or perhaps a biotope aquarium that precisely mimics the specific habitat of a given species of fish? Alternatively, you may be looking to create a fully planted aquascape. There is a multitude of options to consider, one of the many factors that make the fishkeeping hobby so rich and rewarding.

Do you live in a hard-water or soft-water area? What is the chemistry of your tap water? I would advise a beginner to select livestock based on this chemistry to help simplify maintenance. If not, you need to consider how to prepare your aquarium water to match those required by your chosen livestock. There are numerous methods to achieve this but be aware it will add a further degree of work and understanding during routine maintenance of the aquarium.

Once you have made your choice of the type of aquarium set-up and fish that you intend to care for, then you need to research the essential items listed above and select those best suited for your situation. Revisit our article to help you with your choices.

Take your time and continue to do your research and ask questions until such time you are comfortable with your choices. Remember you are responsible for the welfare of the fish and other livestock that you decide to keep.

Step 2 Choosing a Location

It is vital to get the location and positioning of an aquarium right. It needs to be away from direct sunlight and heat sources such as fires or radiators. You should also position the aquarium away from sources of noise and vibration such as televisions and music centres.

Equally, before finalising the location of the aquarium, you must ensure that the floor and cabinet are sufficiently sturdy and robust to support the combined weight of the aquarium, equipment, décor and importantly water. It will be heavier than you think!

For example, a typical 90-litre aquarium will weigh approx. 15Kg before being filled and approx. 105Kg+ when filled with water alone and potentially considerably more when adding the weight of the cabinet, substrate and décor.

Do not forget you will need power sockets for equipment including the filter, lighting and heater thermostat. Remember, water and electrics do not mix!

Finally, also remember to locate it where you can sit, view, relax and enjoy the aquarium and its occupants!

Step 3 Set Up Aquarium & Cabinet

The surface that you place the aquarium needs to be flat and level. Many dedicated aquarium cabinets have adjustable feet to level the aquarium. If not take the time to adjust the aquarium-cabinet or other sturdy support until it is level. If you do not, you will regret it later as the water level in the tank will reflect any discrepancies.

Most aquariums require a mat under the glass bottom to protect the base from damage due to an irregular surface. If your aquarium has a floating-base, i.e. a rim or legs purposely keeping the base pane elevated, then a base mat is not required or advised.

Position the aquarium and cabinet, so there is sufficient room behind or at the sides for pipework and cables. Think about the space and the access you need for maintenance.

Clean the aquarium before final positioning. If new a simple wipe with plain water to remove any grease or dust is all that is required. Do not use any soaps or other liquid detergents, or anything abrasive. If the tank is second-hand, then please refer to our article on ‘Second-Hand Aquariums’ which includes additional advice on cleaning the tank and ensuring it is watertight.

Step 4 Add Substrate

Clean your decorative gravel or sand as directed by the manufacturer. The best method for this is generally to place the gravel or sand in a bucket and run water from a hosepipe through it until it runs clean. Many gravels can be very dusty, and if you miss this step, it can cause the aquarium water to become very cloudy once added, which in turn will start to clog your filter once installed.

Once clean, carefully place the decorative gravel or sand on the bottom of the tank and create a gentle slope from the front to the back. In most circumstances a maximum depth of 2-3 inches (approx. 5- 8cm) at the rear of the aquarium is sufficient.

If you have decided to use a specialised planted aquarium soil again follow the specific manufacturer’s instructions, but typically it will not need to be washed before adding.

If it is a complete substrate, it will be used on its own as directed by the manufacturer. As with decorative substrates, place it on the tank bottom, again with a gentle slope from front to back.

Note if the manufacturer has designed the chosen specialised planted aquarium substrate for use as a nutrient-rich layer, then it must be ‘capped’ with either an aquarium soil as above or decorative gravel to avoid nutrients leaching out too quickly.

Step 5 Decorate – Hardscape

As with gravel clean and then add your chosen décor (hardscape) to the aquarium. Take your time to carefully position your decorative items to create the landscape you desire. Remember to include lots of interest and places for your fish to swim and shelter.

If your items are prone to floating in the water, such as some woods, then it makes sense to pre-soak. You may also initially need to weigh down items with large rocks until they have absorbed enough water to sink of their own accord.

A common mistake is not to include decorative items with sufficient height. Also, take care not to position any items too close the aquarium sides as this will make it more difficult to clean the glass during your aquarium maintenance sessions.

Step 6 Install Equipment

Start to position your equipment, but do not switch it on! It is often easier to position and fit, for example, filter pipework before filling the tank with water.

The majority of aquarium heaters/thermostats by design need to be fully submerged. Follow the guidance from the manufacturer regarding orientation and position, but also try to hide behind the aquarium decoration. Inline heaters, by contrast, should be installed in the filter outlet pipework.

When positioning an internal filter, place it to ensure the best possible circulation throughout the tank. When fitting an external canister filter, place the inlet and outlet pipes at opposite ends of the aquarium again to promote good circulation. In both cases open the filters before positioning to check that the filter media is located correctly and not sealed in temporary packaging – don’t laugh, I have seen this happen.

Depending on the style of the thermometer, it is best to place it where easily viewable, but not distracting.

Lighting may have come already fitted with your set-up inside the aquarium hood, but if not now is the time to position it as directed in the manufacturer’s instructions.

Remember do not switch on the equipment yet, the design of filters and heaters require that they run submerged or with water running through them.

Step 7 Add Plants [Optional]

If you are adding live plants, and we recommend that you do, then this is the time to add them as long as you intend to follow on immediately with the next step. Read our article on the ‘Benefits of a Planted Aquarium’ to understand why the use of live plants will help create a more stable environment for your fish.

As a beginner, a selection of easy to grow plants is the best choice. Stem plants such as Hygrophila Siamensis 55B and species such as Cryptocoryne wendtii both need to be planted into the substrate. In contrast, attach epiphyte species such as Java fern and Anubias to wood or other pieces of décor in the aquarium.

If you are not using a specialised aquarium soil or plant substrate, then this is an excellent time to introduce some plant tabs - fertilisers in pellet form. Insert these into the inert gravel or sand in the areas where you have planted.

Step 8 Treat and Add Water

If using tap water, you will need to use a water conditioner to neutralise harmful chlorine and chloramine, incorporated as disinfectants by many local water authorities. Perfectly safe for human consumption, but toxic to aquatic organisms.

Add the treated water slowly to the aquarium. It is best to either use some plastic sheeting over the substrate and décor or add the water via a colander to help dissipate the water stream and avoid the substrate and plants being disturbed.

Now that you have filled the aquarium with water, it is time to switch on the equipment and check that everything is working correctly. The filter pumps may gurgle and splutter as they expel air, but once they settle, they should run reasonably quietly. Check the flow rate from the filter to ensure it is working at its optimum.

Time to leave the aquarium alone for a while, but repeatedly check all-around the tank and any external pipework for leaks. The aquarium will gradually come up to the set temperature. Continue to monitor this for a couple of days and if necessary, adjust the heater thermostat, when switched off, to achieve the desired water temperature.

Always remember to turn off the electrics if working inside the aquarium.

Step 9 Cycle Aquarium

By far, this is the most crucial step in the process of setting up a new aquarium. As it stands, your aquarium and filter are sterile. There will be little to no beneficial bacteria on the surface of the decorative substrate or filter media to support the nitrogen cycle.

Do not be tempted or swayed by others to add any fish at this point - this is a sure way to cause the untimely death of fish as a result of New Tank Syndrome.

The best method to prepare your tank for fish and other livestock is using a ‘Fishless Cycle’. Refer to our articles on ‘Understanding the Nitrogen Cycle’ and 'Fishless tank Cycle – Step-by-Step Guide’ to gain a better understanding of what is required and details instructions on the process required.

Not maturing the aquarium filter is the stage where most beginners go wrong. As soon as the aquarium is set-up and full of water, there is an overwhelming temptation to get your first fish. Unfortunately, you need to resist this if you want to avoid the all too common issues of experiencing problems with the aquarium water chemistry, stressed and diseased fish and ultimately the death of your fish.

How long will a fishless cycle take? Unfortunately, it is not an exact science as there are many variables, but typically it can take anywhere from approximately 2 to 6 weeks. For the best results read and follow our 'Fishless tank Cycle – Step-by-Step Guide’ which will guide you through the process.

Step 10 Add Fish

Well done! If you have successfully followed all the steps above, then you are now at the exciting stage where you can start to add your fish and other chosen livestock.

It is important to start adding fish as soon as you successfully have completed the fishless cycle, as it will be their waste that continues to support the nitrogen cycle. However, do not be tempted to fully stock too quickly.

Now is the time to sit back and enjoy all the benefits of your new aquarium - but be sure to read our article on how to maintain a healthy aquarium and our maintenance tips.

Author: Stewart Kessel CChem, MRSC

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