Buying & equipment

Keeping aquarium fish is an attractive and varied hobby. It allows you to observe a small ecosystem from up close, learn the behaviour of different species of fish and enjoy a rainbow of exotic colours. Setting up an aquarium also provides an ideal opportunity to design your own underwater landscape. 

First steps 

Freshwater aquarium

Community tanks are the most common type of freshwater aquarium. These contain various different, usually tropical, ornamental fish and a number of different plants that all have similar requirements. A biotope tank, by contrast, contains fish from one or more closely related species (e.g. Mbuna cichlids).

Equipment checklist

  • Aquarium with cover and light tube 
  • Aquarium underlay, e.g. sytrofoam board (approx. 0.5 - 1 cm thick) or soft rubber
  • Gravel
  • Decoration: xylolite, porous rock, aquarium roots, aquatic plants and fertilizer
  • Filter: Internal or external filter with filter substrate 
  • Adjustable heater and aquarium thermometer 
  • Magnetic glass cleaner or (special) sponge for algae removal
  • Water treatment, such as Aqua-Bon® 6 in 1 and filter bacteria
  • Hose for changing water
  • 10 litre bucket used solely for cleaning your aquarium
  • Timer for aquarium lighting
  • Food suitable for your species of fish

The right spot

You should set up your aquarium in a spot that you can observe from a comfortable position. Avoid direct sunlight: this can promote the growth of algae and result in the water becoming too warm in summer. It is therefore best not to place the aquarium too close to a window.
When setting up a large tank in particular, you must ensure that the stand is capable of bearing the weight. Even smaller tanks can be heavier than you might expect: each litre of water weighs 1 kg and adding gravel, stones and other decoration can soon result in a tank weighing more than 80 kg. The safest option is to place your aquarium on a special aquarium cabinet that has been designed to accommodate the additional weight.
You should place your aquarium on a styrofoam base or other special underlay to compensate for any minor bumps on the surface of the stand.

Setting up your tank

When setting up an aquarium, you need to create a living environment suitable for the fish and plants you intend to keep. To create a "biological balance", you need the right equipment to establish a properly functioning cycle that involves fish, plants, water and micro-organisms. 

Overview of the most important steps

1.    Gravel and decoration

Wash the gravel in fresh water (until water passing through the gravel runs clear). Mix around a third of this gravel with a nutrient medium and distribute it evenly along the bottom of the tank. Spread the remaining gravel on top. The base of the tank should be covered with gravel to a depth of around 3 - 6 cm, rising slightly towards the rear. Scrub clean all decorative items (stones, roots etc) using hot, clear water and push them down into the gravel. If you are keeping fish that rummage through the gravel, ensure that all structures are firmly positioned on the base of the tank and cannot tip over (fix them in place with silicone if necessary). Round gravel is also recommended for this type of fish.
You can then fill around of the third of the tank using tap water at room temperature that has already been treated with Aqua-Bon® 6 in 1 or a similar product to prepare it for your fish. You must check the water values at regular intervals to ensure they meet the needs of your fish.

2.    Set up the aquatic plants

Before placing aquatic plants in the tank, you should remove any plant substrate on the roots and use a pair of scissors to cut back the roots by about one quarter. Fast-growing plants with long stems (e.g. cabomba) are best used as background plants. Press them down into the gravel and use a pebble to hold them in place. Individual plants with a wide, rosette shape (e.g. Amazon sword) look particularly attractive when placed in the centre of the tank. Simply use your finger to make a hole in the gravel and lower in the plant. 
To prevent your view of the fish from being obscured, it is best to use only small plants (e.g. anubias) at the front of the tank. Epiphytes are also highly decorative when placed in the foreground. Use a nylon thread to attach them to stones or roots. 

3.    Fit a filter and adjustable heater

Note: When working with electrical equipment, always remove the plug from the mains before placing your hand in the water. 
You can now fill the aquarium with prepared tap water up to around 3 - 4 cm below the rim. Attach the heater to one of the rear corners of the tank using suction cups. If you are using an in-tank filter, fill it with filter material and attach it to the opposite corner. If you are using an external filter, place the suction tube in the tank. Mount the outflow horizontally on the rear or side of the aquarium so that it is level with the surface of the water. 
Place a thermometer on the front or side of the aquarium so that you can check the temperature at any time. Most species of tropical ornamental fish prefer temperatures of 20 - 28°C. The fish expert in your pet shop will be able to provide further information about the specific needs of each species of fish. 

4.    Switch on your equipment

Once you have placed all of your equipment in the tank, you can carefully put on the cover. Then connect the filter, heater and light to the mains. Use a timer to provide a regular illumination period of 10 - 12 hours. 

5.    Cycling phase

Important: Before you put any fish in the tank, it will need to "cycle" for around 3 - 4 weeks. During this period, essential micro-organisms build up in the filter sponge and gravel. These break down harmful substances and maintain the biological balance in the aquarium. You can give your aquarium a helping hand during this stage by "seeding" the filter sponge with filter bacteria. 

6.    Select your fish 

After the 3 - 4 week cycling phase, the conditions in you aquarium will be ready for your fish. You should consider the following in your selection:

  • The behaviour and requirements of the species you choose must be suitable for the water quality in the tank and the food you provide 
  • You can check the water values using a testing kit from the pet shop  (see also "Water treatment and partial water changes")
  • Different species of fish prefer to live in different parts of the tank. Your aquarium will look particularly lively if it has fish in the top, middle and bottom regions.
  • As a guide, you should have a maximum of 1 cm of fish for each 4 litres of water. A densely populated tank will exhibit greater fluctuations in water values, over-fertilisation and increased algae growth: all of which pose an increased risk to the health of your fish

7.    Place your fish in the aquarium

Ornamental fish should be introduced into your aquarium carefully to avoid "relocation shock". To even out the temperature and water qualities, you should first place the bag containing your fish into the tank. Do not let any water flow in or out and make sure that the bag is not directly below the light. 
After around 15 minutes, replace around one third of the water in the bag with aquarium water or top up the bag with this amount. Repeat this action two more times at intervals of 15 minutes. You can then use a net to place the fish carefully into the aquarium. Since the water in the bag from the pet shop may contain medication or micro-organisms that are not compatible with the ecosystem in your aquarium, you must pour it away separately.

The right spot

You should set up your aquarium in a spot that you can observe from a comfortable position. An aquarium provides an attractive point of interest in any room.

Do not place the aquarium too close to a window. Avoid direct sunlight: this can promote the growth of algae and result in the water becoming too warm in summer.

When setting up a large tank in particular, you must ensure that the stand is capable of bearing the weight.

You should place your aquarium on a styrofoam base or other special underlay to compensate for any minor bumps on the surface of the stand.

Caring for your fish

The quality of the water in your aquarium determines the quality of life for your ornamental fish. Your fish will only remain happy and healthy if the biological and chemical processes in the water are functioning correctly. Aquarium owners must therefore aim to provide a biological balance in the aquarium through regular maintenance measures. 

Water treatment and partial water changes

Rivers and lakes are cleaned naturally by the flow and replenishment of water. In an aquarium, however, the effects of such natural cleaning processes are very limited. You therefore need to use high-performance filters and perform partial water changes on a regular basis to reduce the level of toxic substances in the water.
Exotic ornamental fish have evolved to meet the conditions in which they live in their natural habitats. To ensure that your aquarium reflects these conditions, you must treat the water when first setting up the tank and during the regular partial water changes.  Aqua-Bon® 6 in 1 water treatment binds chemicals and converts normal tap water into aquarium water suitable for your fish. This protects the sensitive gills and mucous membranes of your fish. 

Optimal filtration reduces toxins

Together with partial water changes, permanent filtration is one of the most important requirements for ensuring clean and clear water in your aquarium. The filtration cycle is divided into two stages, each of which involve specific filter materials.

  • Mechanical filtration (pre-filtration) removes organic residues such as dead plant matter, food remnants and fish waste. However, it must not be possible for large particles to enter the filter.
  • Biological filtering (post-filtration) is performed by micro-organisms that take up home in the pores of the filter materials.

During biological filtration, the micro-organisms convert nitrogen compounds (e.g. the waste products from protein digestion) into non-toxic nitrate over a number of stages. The first stage involves the production of non-toxic ammonium (NH4+) or, if the pH values are above 7.5, toxic ammonia (NH3).

The ammonium or ammonia is then converted into nitrite (NO2), which is likewise toxic, before finally being broken down into non-toxic nitrate (NO3). Nitrite is very hazardous to fish. Although nitrate is less hazardous, it is a plant nutrient that can promote the growth of algae. Excessively high levels of nitrate or nitrite can quickly be corrected by performing a partial water change. Over the long term, however, you need to identify and reduce the causes of contamination.

Since these chemicals are highly toxic, you should check the toxicity values and other water values on a regular basis to prevent the water from becoming contaminated and endangering your fish's health.

Testing and adjusting water values

Different species of fish have different requirements for the hardness and pH values of the water in which they live, based on the type of water in which they would live in the wild. 
Most freshwater fish require a carbonate hardness of 3° - 12° dKH on the German carbonate hardness scale, and soft to medium-hard water with a total hardness of 4° - 14° dGH on the German total hardness scale. The carbonate hardness is also important for ensuring a stable pH value and should never fall below 3° dKH. 

The pH value indicates the water's acid content: Values below pH 7 are acid; values above this are alkaline. Cichlids from the East African lakes require an alkaline pH value of around 8, for example, whereas apistogramma from the Amazon region live in watercourses with acid pH values of up to 5.5.

Regular maintenance and cleaning

The maintenance activities needed for a properly set up and cycled aquarium do not require a great deal of time if performed on a regular basis:

  • Daily: Check the equipment and temperature. Observe the behaviour and appearance of your fish (changes can indicate an illness)
  • Approximately every 14 days: Before carrying out a partial water change, first check the water values (pH, hardness, NO2, NO 3). Then replace between 10 and 30% of the aquarium water depending on the number of fish. Use tap water that has been brought up to the water temperature of the aquarium and that has been treated to meet the needs of your fish. Before topping up, also clean the glass of the aquarium using a magnetic algae cleaner.
  • Plant care: Cut back fast-growing plants with long stems to 2/3 of their length if they are growing along the surface of the water.
  • Filter maintenance: Clean the mechanical filter when performing a partial water change. Carefully rinse out the biological filter material around every 3 months using aquarium water (never use cold tap water) to avoid disturbing the necessary micro-organisms.


The perfect diet

The tropical and sub-tropical waterways from which freshwater fish originate naturally provide a variety of essential nutrients. The majority of the food comes from the underwater environment, for instance mosquito larvae, daphnia, tubifex and plant matter (algae growth). However, food also sometimes enters the water from outside: insects, fallen flowers, berries etc. 

Feeding aquarium fish

During the course of evolution, each species of fish has adapted to eat the range of food available in its natural habitat. The food you provide to aquarium fish should therefore reflect this natural diet and provide fish with all required nutrients in the required quantities and combinations. Care should be taken, however, to avoid contaminating the water with superfluous nutrients. 

Different fish specialise in eating certain types of food – sometimes even within the same family of fish. Some fish are primarily plant eaters, whereas others are predatory or omnivorous. The majority of fish usually kept in aquaria are omnivores.

Vitakraft's approach to ornamental fish food is inspired by nature and its products are designed to meet all nutritional requirements of individual species of fish. The nutrients in the food are very easily digested, which prevents the water being contaminated unnecessarily by excess nutrients in the fish's waste.

Species-appropriate food and its properties in water

Each species of fish lives in a certain region of the water, which is also where it eats its food. Bottom-dwelling catfish, for example, have a mouth that points downward so that they can suck up nutrients. Fish from the upper water regions (hatchet fish, guppies) eat from the surface and have a mouth that faces upwards. Fish from the central regions have a mouth that faces forwards.

Depending on the way in which fish take in their food, the food provided will need to sink, float or remain suspended in the tank. The scent of the food is also important as fish find it using their sensitive olfactory organs. Vitakraft fish food for ornamental fish has special qualities that take into account the different requirements of individual aquarium fish. 

Building blocks for the perfect diet

  • Fats provide the main source of energy and are also required to build up energy reserves. Vitakraft food is particularly rich in essential unsaturated omega-3 fatty acids derived from crustacean and fish oils.
  • Some fish are also able to use carbohydrates as a source of energy. From a biochemical perspective, carbohydrates also include (dietary) fibre which plays a particularly important role in ensuring healthy digestion in plant-eating fish.
  • Proteins and amino acids are the driving force behind fish metabolism and enable muscle formation, growth and the creation of other tissue. Vitakraft ornamental fish food contains a precisely dosed combination of proteins and the maximum amount of essential amino acids.
  • Providing the right quantity of high-quality vitamins is essential for a wide range of metabolic processes and helps the body's natural defences to fight off illness.
  • Vitakraft ornamental fish food contains Immune Active, a specially developed mixture from beta-glucans, multivitamins and stabilised vitamin C to strengthen the immune system.
  • Fish also require food colourings (e.g. Astaxanthin) to retain their species-specific colour, which plays a vital biological role in their behaviour. In addition to providing a means of communication with fish of the same species, the intense colours of ornamental fish are also pleasant to behold.


 Feeding tips

  • It is best to feed your fish a small amount once or several times each day. Never provide more than the fish can eat within a few minutes.
  • Provide a varied diet: this particularly applies to community tanks.
  • Do not feed your fish immediately after performing tank maintenance (changing the water or cleaning the glass).



Alternative Title

Bristlenose Catfish, Bushymouth Catfish (Those found in aquaria are usually hybrids of this and other catfish, often referred to simply as ‘Pleco’.)

Scientific Title

Ancistrus dolichopterus


The Bristlenose Catfish has the flat body shape typical to catfish. Length: grows to 15 cm.


The Bristlenose Catfish originates from the Amazon River Basin


The catfish is a loner although keeping several Bristlenose Catfish together is usually not a problem. When breeding, it is the male that takes on the parental role, protecting the eggs in his cave until after they have hatched.


These fish are often seen eating algae which form on the tank glass, decorations and gravel. Their diet should be supplemented with sinking pellets or wafers only.


The catfish is a very robust fish that is able to tolerate a broad spectrum of tank conditions. The temperature can be between 18 and 30°C with a pH of between 6 and 8. It is often recommended as a robust first fish for new aquarists.

Dwarf Gourami

Scientific Title

Colisa lalia


The males have strong red and silver-blue stripes, whereas the females are a more understated silvery colour with a light shimmering red and pale stripes. Breeders have created different colour variations, such as neon blue or red, for example. Size: grows to 5 cm.


The Dwarf Gourami originates from rivers in India.


The Dwarf Gourami is a social fish, preferring to live in pairs or a small harem. The fish may breed in calm water with plenty of vegetation. The male builds a floating bubble nest in which the eggs are laid.


In the wild, Dwarf Gourami eat insect larvae and other micro-organisms. In an aquarium, they eat protein-rich flake food and, from time to time, an animal-based individual food such as Daphnia.


Water temperature: 24 to 30 °C, pH: 6 to 8

Special features

Do not keep with aggressive fish as the Dwarf Gourami is vulnerable to fin nipping.


Alternative Title

Freshwater angelfish

Scientific Title

Pterophyllum scalare


The angelfish is a laterally compressed fish with elongated triangular dorsal and anal fins. In the wild it has a silvery body with dark, vertical stripes. Domestic angelfish have been bred and crossbred for several decades, resulting in many colour variations, with and without stripes or spots. Size: grows to 15 cm long, 25 cm high.


All Pterophyllum species originate from the Amazon River, Orinoco River and Essequibo River basins in tropical South America.


At breeding time, adults pair off and become very territorial. Eggs are generally laid on a leaf, which is carefully cleaned beforehand.


In the wild, angelfish tend to eat live insect larvae and micro-organisms. In an aquarium, they need to be fed a protein-rich flake food and, from time to time, an animal-based individual food such as Daphnia.


Water temperature: 25 to 30 °C, pH: 5 to 7.5

Special features

Do not keep with aggressive fish that are known to nip fins or very small fish.