A Complete Guide to Starting a New Freshwater Aquarium

Getting into the hobby for the first time can be confusing. Hopefully this guide will help you enter the hobby and become a successful aquarist!

Freshwater Aquarium Fish


The first step of your journey is to decide on the size of the fish tank. You are essentially creating a miniature ecosystem, at least when compared to the real thing. The larger the volume of water, the more stable and forgiving your system will be. Therefore it is easier to maintain a larger aquarium.


Once you have decided on the tank volume, you can begin to plan what fish you would like to keep. Some fish, such as goldfish, can grow very large and may soon outgrow a small tank. If you choose a tank on the smaller side, we recommend that you keep small fish that stay small. Fish also come from different areas around the world such as Africa, South and Central America, Asia and Australia and thus may require certain water parameters to thrive. As a general rule, we do not recommend mixing fish from different areas together as they may also have different levels of aggression. Some fish can also be predatory and territorial therefore, when in doubt, please ask our staff members for guidance.


Once you know what type of fish you would like to keep, you can then decide on the filtration. Certain fish can produce a lot of waste while others don't produce much at all. A filter is the backbone of your fish tank. This is where the waste from your fish gets collected and broken down into less harmful substances. The best type of filter posses the following three components:

  • Mechanical Media - These consist of sponges and wool of different coarseness. They will capture big particles of waste and break them down into smaller pieces. These waste particles can be removed by rinsing the sponge and/or replacing it on a weekly/monthly basis.
  • Chemical - This component generally consists of activated carbon or different resins which can be used to remove organics, bad smells and polish your water. For example: Tannins from driftwood and the colouring from fish food can stain your water. Using activated carbon or resin can help maintain the clarity of your water. There are also different chemical absorbents for different needs such as phosphate remover media.
  • Biological - This component is perhaps the most important part in your filter. It is essentially just a house for beneficial bacteria to live in. Fish produce ammonia (NH3) as their waste; and high level of ammonia can cause gill and internal organ damage to your fish. The easiest way to neutralize ammonia in your fish tank is to grow beneficial bacteria which will breakdown ammonia into nitrite (NO₂) and then into nitrate (NO3-). Nitrate is the safest form of nitrogenous waste in your fish tank and is generally used by plants to grow or removed through water changes.

Now that we have discussed the different elements to a filter, here are 5 types of filters that you can choose from:

  • Sponge Filter - The most basic and gentle. Ideally only used for breeding, quarantine and in a shrimp tank. Need to be cleaned very regularly to remove blockages.
  • Internal Filter - A step up from a sponge filter. Most internal filters do allow for chemical filtration and primarily run on sponges which means the mechanical and biological filtration share the same area. However, during cleaning, a lot of beneficial bacteria will be lost. Ideal for nano tanks with small fish, shrimp or planted tanks.
  • Hang-On Filter - A good option for small tanks. Hang-on filters generally have the three stages of filtration; mechanical, chemical and biological and a gentle flow. The downside is the filter hangs over the back of the tank and you will not be able to cover the entire top of the tank. An ideal choice for goldfish due to generally having low return flow and also the ease of cleaning.
  • Canister Filter - The best filtration option. Canister filters have large media chambers and usually have separate trays for different filter media. Perfect for everything and very versatile.
  • Sump Filter - This is the perfect option when keeping fish that produce a HUGE amount of waste. They can be quite tricky to setup and may need to be customized. Ideal for predators, African cichlids and goldfish.

Aquarium Filter Types

A general rule of thumb is to aim for 4 times turnover rate for low density tanks and 6-10 times turnover rate for high density tanks (for example: if your tank volume is 20L, a sparsely populated tank would need an 80L/hour filter and a high density tank would need a 120-200L/hr filter).


    Most of the fish species come from warm tropical environments and will require a heater to maintain 24-27°C especially during winter. This can be achieved by using a heater. Aquarium heaters are equipped with a built in thermostat and can regulate the temperature in your tank. There are some cold water species such as minnows, zebra danios, medakas and goldfish. These fish don't require heating. Most cold water species can also survive in tropical water without issues, however there are some exceptions such as Axolotls. A chiller might be necessary to keep Axolotls happy. Ideally, put a thermometer in your tank to make sure that your equipment is giving the correct readings.


    Adding oxygen into the tank can be done by using an aerator. An aerator is basically a device that pumps air through a thin air line tube into the tank to aid oxygen exchange. Cold water fish species can typically survive in warmer water if more oxygen is provided through aerating the water. A better way to provide enough oxygen to your tank is by keeping live plants. In a well planted tank, aeration is not necessary and may in fact inhibit your plants growth.


    There are many lighting options and the price can range from $50 to $1500. Here are a few factors to consider when choosing your aquarium light:

    • Purpose - Basic illumination or plant growing.
    • Power - Plants have different light requirements. Some plants require strong brighter light while others grow in the shade.
    • Spread - The power and lens on the light determine the overall spread and penetration of the light. The deeper and wider the tank, the higher the lighting needs.
    • Mounting Option - Lights come in different lengths and have different mounting options.
    • Function - Some lights can be programmed using Bluetooth or wifi which means you have the power to control the intensity as well as color spectrum.

    For more in depth guide on lighting can be found here. (not available yet).


    The choice of aquarium substrate or gravel ultimately depends on what type of fish or aquarium setup you would like to keep. Here are a few different substrate options:

    • Inert Gravel / Sand - Normal non fertilised gravel that is typically 1-3mm in grain size. This type of gravel typically doesn't alter the water chemistry too much (but may still buffer your water a little).
    • Coral Sand - Coral sand is basically calcium carbonate. This type of sand will typically make your water more alkaline (increase pH) and hard (increase kH and gH). Coral sand is ideal for most African Cichlid species.
    • Plant Soil - Pelletised soils are the best option to use if you want to focus on keeping plants. Ideally, only use the soil in areas where you are going to have plants. If soil remains uncovered, bottom dwelling fish and catfish may stir the soil too much and cause your water to be cloudy when the soil breaks down.
    • Shrimp Soil - There are special soils designed for keeping freshwater shrimp. Typically these soils do not contain too much fertilizer and will maintain the right acidity and softness of the water.
    • Colored Gravel - Preferably not...but if you must...


    Fish come from different areas and may require different conditions, however most fish in the aquarium trade have been bred in captivity and are more adaptable compared to wild collected fish.

    In our opinion, stability is much more important than trying to aim for a specific number for example PH 6, KH 2 and GH 1.

     A little chemistry lesson

    PH is the measure of acidity in your water. PH 7 is Neutral, PH <7 is Acidic and PH >7 is Alkaline.

    KH measures the amount of carbonates and bicarbonates in water and this affects the buffering capacity of the water. KH helps neutralize acids and it prevents PH from changing too quickly. The higher the KH, the more stable the PH will be.

    GH is essentially the amount of dissolved minerals in the water such as calcium and magnesium. Low GH water is considered soft and High GH is considered hard water.

    Ultimately, the aquarium furniture (substrate, wood, rocks, plants, filter media and even the number of fish, quantity of feeding and routine) will determine the overall parameters of your water. 

    Depending on where you live, in general the PH of our tap water is around 7.5-7.8. Overtime, due to plant decay, tannins from driftwood and fish waste, the PH of your water drops. A 20% water change with your tap water is generally enough to raise your PH. Ideally, we recommend to perform a routine 20% water change weekly.

    There are liquid and powder chemicals to adjust these parameters but it's more ideal to change the "furniture" in your tank to achieve your goal such as adding more driftwood or use soil if your goal is to have a lower PH and softer water. Adding coral rubble helps to increase PH, GH and KH. As these elements are permanently in the aquarium when you add regular tap water to the system, the water parameters will stay the same. Whereas using chemicals to achieve the same result will create a rollercoaster effect as the parameters fluctuate and plummet with dosing. 


      • Avoid placing the tank in direct sunlight as this lead to algae growth and potential heat fluctuations.
      • Make sure the cabinet is level.
      • Make sure there is foam or cushioning underneath the glass fish tank.
      • Add in your gravel / soil.
      • Arrange the hard scape (rocks and wood placement)
      • Once you are happy with the scape, it's time to fill the tank with water.
      • Install all the electrical equipment (filter, heater, light and aerator).
      • Add water conditioner to remove chlorine and chloramine from the tap water.
      • Add beneficial bacteria. Your tank will start it's cycle when you add this bacteria. Typically, it takes 2-3 weeks (sometimes longer) to cycle. During this period, ammonia levels will rise and the first population of bacteria will start to feed on the ammonia and produce nitrite. During the second or third week, a second bacteria which feeds on nitrite and converts it into nitrate will come to life. Once you have no more ammonia and nitrite, your tank is considered cycled and you can start adding fish into the tank. It is important not to add too many fish in one go as the bacteria population will need to grow to accommodate to the new bio load (waste). It's best to keep feeding to minimal too during the first 3 months as your bacteria colony may still need to develop. A mini cycle or a small spike in ammonia is common during the first 3 months but this rarely become a problem.


      • Daily - Feeding, Check fish behaviour.
      • Weekly - Perform 20% water change. Even though the bacteria in the filter converts ammonia into nitrate, this chemical can accumulate if not removed either by plants as part of their fertiliser needs or through water changes. 
      • Monthly - Clean filter and replace any rancid filter media.
      • Quarterly - Clean filter impeller and other equipment.


      1. How many fish can I keep in a tank?
      2. How much should I feed the fish?
      3. What should I test my water for?

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