There’s a reason why aquaristics is one of the most beautiful and versatile hobbies. You can observe a small ecosystem up close, learn about the behaviour of the different fish species, and marvel at their exotic colours. There are also many opportunities to implement your own design ideas when setting up your aquarium.

First steps

The freshwater aquarium

Among freshwater aquariums, community tank is the most common. In this tank, various mostly tropical ornamental fish species and different plants are kept; these are all similar to each other in their requirements. A species tank, on the other hand, is home to fish of one or more closely related species (e.g. mbuna cichlids).

Equipment check-list

• Aquarium with cover and fluorescent tube
• Aquarium substrate (e.g. polystyrene board (approx. 0.5–1 cm thick) or soft rubber)
• Substrate
• Decoration: rocks, aquarium root, and water plants
• Filter: Internal or external filter with filter substrate
• Regulator heater and aquarium thermometer
• Magnetic disk cleaner or sponge (special) to remove algae
• Water conditioner and filter bacteria
• Hose for water change
• 10-litre bucket used exclusively for aquarium maintenance
• Timer for aquarium lighting
• Feed, suitable for the chosen fish species

The right location

The aquarium should be set up in such a way that you can watch the fish from a comfortable place. However, direct sunlight can promote algal growth and heat up the water too much in summer. It is therefore better not to place the aquarium too close to the window. Especially for larger tanks, the load-bearing capacity of the location must be considered in the planning. Even small tanks have a considerable weight: One litre of water weighs 1 kg – plus substrate, stones, and other decorations. This can quickly add up to more than 80 kg. The safest place for an aquarium is therefore on a special aquarium base cabinet, which takes into account this weight in the static structure. The aquarium should be placed on a polystyrene base or other special base. This will compensate for any minimal unevenness of the storage surface.

Furnishing the aquarium

The purpose of setting up the aquarium is to create a species-appropriate habitat for fish and plants. The desired “biological balance” depends on the interplay between fish, plants, water, and micro-organisms as well as the technical equipment.

The most important steps at a glance

1. substrate and decoration

Mix about one third of the substrate washed with clear water (no turbidity should remain in the water when rinsed) with some nutrient medium, and spread it evenly on the bottom of the tank. On top of this, add the remaining substrate. The bottom of the tank should be covered with approx. 3–6 cm of substrate rising towards the back. All decorative objects such as stones and roots are scrubbed off with clear, hot water and pressed into the gravel. For fish that rummage through the substrate, make sure that the structure stands firmly on the aquarium floor and that nothing can tip over (fix with silicone if necessary). For such animals, a round-grained substrate is also preferable. The tank is then filled about one third full with tempered tap water, which has been prepared beforehand to suit the fish. Depending on the needs of your future fish, the water values must be checked regularly.

2. inserting the aquatic plants

Before insertion, remove the plant substrate adhering to the roots and shorten the roots of the plants by about one quarter with scissors. Fast-growing stem plants (e.g. hair nymphs) are excellent as background plants. Press them into the substrate, and weigh them down with a pebble. In the middle area, single rosette plants growing in width (e.g. the Amazon sword plant) look particularly beautiful. To plant, simply bore a hole in the gravel with your finger and place the plant inside.  To avoid blocking the view of the fish, only small-growing plants such as the small spear leaf should be used for the foreground. The perching plants also look quite decorative in the foreground. They are attached to stones or roots with a nylon thread, which can also be used to tie in java fern, among other things.

3. attach filter and heater

Note: Always unplug technical equipment before reaching into the water!  Now fill the aquarium with prepared tap water up to about 3–4 cm below the rim. Then attach the control heater with suction cups in one of the rear aquarium corners. In the other corner, attach the internal filter filled with filter material or – if an external filter is used – the intake pipe. The corresponding outlet is mounted horizontally at the height of the water level on the rear aquarium pane or on the side.  The thermometer is mounted on the front or side of the aquarium in order to be able to check the water temperature at any time. Most tropical ornamental fish species prefer temperatures around 20–28°C. Ask your pet shop about the more exact needs of the particular fish species.

4. start-up of the aquarium

After all technical devices have been connected, the cover can now be carefully placed on the tank. The filter, heater, and lighting are then connected to the electrical circuit. A timer ensures a regular lighting period of 10–12 h.

5. run-in phase

Important: The fish should be introduced only after a “run-in phase” of about 3–4 weeks. During this time, the valuable micro-organisms are formed in the filter mass as well as in the substrate. They take care of degrading pollutants and the biological balance in the aquarium. This process can be effectively supported by “inoculating” the filter mass with filter bacteria.

6. selection of fish

After 3–4 weeks of the run-in period, a suitable habitat for the fish has been created in the aquarium. The following must be taken into account when selecting the inhabitants:

• The fish species must match in their behaviour as well as their water quality and dietary requirements.
• The water values can be checked with a test kit from the pet shop (for more information, see “Fish-friendly water treatment and partial water changes”)
• Each fish species lives in a preferred water region. The aquarium appears most lively when the upper, middle, and lower water regions are inhabited.
• As a guideline, a maximum of 1 cm of fish per 4 l of water is recommended. A more densely populated tank tends to cause fluctuations in water values, over-fertilization, and increased algae growth and thus carries an increased risk of disease for the fish.

7. placing the fish in the aquarium

The ornamental fish should be introduced carefully in order to avoid a “transfer shock”. To adjust the temperature and water conditions, the transport bag should first be placed in the tank. No water should flow in or out, and care must be taken that the bag is not placed under the lights.  After about 15 minutes, one third of the transport water is replaced with aquarium water or topped up accordingly. This process is repeated twice after each additional 15 minutes. Then carefully place the fish into the aquarium with the help of a catch net. Because the transport water may contain medications and micro-organisms to which the small aquarium ecosystem is not adapted, it should definitely be discarded.

The quality of the aquarium water determines the quality of life of the ornamental fish. Only if the biological and water chemical processes in the water function properly do the fish remain healthy and full of life. The goal of aquaristics is therefore to ensure a biological balance in the aquarium through regular care measures.

Fish-friendly water treatment and partial water changes

Lakes and rivers clean themselves through natural currents and water exchange. In the aquarium, however, natural cleaning processes can be effective only to a limited extent. Therefore, powerful filtration technology is needed, and partial water changes should be performed regularly in order to reduce the pollutants dissolved in the water. Exotic ornamental fish have adapted to the living conditions in their waters of origin. In order to ensure that they also find these conditions in the aquarium, the water is treated when setting up a new aquarium as well as during regular partial water changes. The Aqua-Bon® 6 in 1 water conditioner binds heavy metals and transforms normal tap water into aquarium water suitable for fish. This protects the sensitive gills and mucous membranes of the fish.

Reduction of pollutants through optimal filtration

Permanent filtration combined with partial water changes is the most important prerequisite for clean and clear aquarium water. The cycle of the filtration system is divided into two stages, each using specific filter materials.

1. Mechanical filtration (pre-filtration) removes organic residues such as dead plant matter, food residues, and fish excretions. Large particles should not enter the filter in the first place!
2. Biological filtration (post-filtering) is carried out by micro-organisms that settle in the pores of the filter materials.

During biological filtration, micro-organisms convert nitrogen compounds (e.g. the waste products of protein digestion) into the non-toxic nitrate via various intermediate stages. In the first step, non-toxic ammonium (NH₄⁺) or, at pH values above 7.5, toxic ammonia (NH₃) is formed.

In the next stage, ammonium or ammonia is broken down into nitrite (NO₂), which is also toxic, and finally into nitrate (NO₃). Nitrite can be quite harmful to fish. Nitrate is less toxic. However, as a plant nutrient, it can promote algae growth. Excessive nitrite or nitrate levels can be quickly reduced by partial water changes. In the long term, the sources should be identified and reduced.

In order to avoid contaminating the water (and thus endangering fish health) and because of the high toxicity, these contaminant levels should be monitored regularly – as should the other water values.

Testing and adjusting the water values

Depending on the water of origin, each fish species has its own requirements for water hardness and pH.  Most freshwater fish need a carbonate hardness of 3°–12° dKH (= German carbonate hardness) and soft to medium hard water with a total hardness of 4°–14° dGH (= German total hardness). The carbonate hardness is also important for the stability of the pH value and should never fall below 3° dKH.

The pH value indicates the acidity of the water: Values below pH 7 are acidic, and values above that are basic. For example, the cichlids of East African lakes require an alkaline pH of around 8. The dwarf cichlids of the Amazon region, on the other hand, live in waters with acidic pH values of up to 5.5.

Regular care and cleaning

The maintenance tasks of an aquarium that has been run in do not take much time – if they are carried out regularly:

1. Daily: Check technology and temperature. Observe the behaviour and appearance of the fish (changes may indicate diseases).
2. Approx. every 14 days: Check water values (pH, hardness, NO₂, NO₃) before partial water change. Then, depending on the fish population, replace 10–30% of the aquarium water with tap water that has been adjusted to the water temperature of the aquarium and prepared in a way suitable for the fish. Before doing so, also clean the aquarium glass with a magnetic cleaner to remove algae.
3. Plant care: Cut off 2/3 of fast-growing stem plants that are already growing along the water surface with sharp scissors.

Filter care: Clean the mechanical filter part during partial water changes. Carefully rinse the biological filter mass only about every three months with aquarium water (never with cold tap water!) so that the valuable micro-organisms are not destroyed.

The basics of nutrition

The tropical and subtropical waters of origin of freshwater fish provide all the essential nutritional building blocks in natural diversity. Most of the food comes from the underwater habitat (e.g. mosquito larvae, daphnia, tubifex, and plant food (algae growth)). But food also enters the water from outside (e.g. insects, fallen blossoms, berries)

Nutrition in the aquarium

In the course of evolution, each fish species has adapted to the particular food supply in its natural habitat. The diet in the aquarium should therefore be based on nature’s example and provide the fish with all the necessary food components in the required quantities and combinations. The water may also not be polluted with superfluous nutrients.

Fish are also known to be different food specialists – sometimes even within the same fish family. There are predominantly herbivorous fish, predatory fish, and omnivores. Most commonly kept aquarium fish are omnivores.

The Vitakraft ornamental fish feed concept follows the path of nature and fully meets the nutritional requirements of the respective fish species. The feed also achieves the best possible nutrient utilization and thus prevents unnecessary water pollution through excretions.

Species-appropriate feed - and its properties in the water

Each fish species lives in a preferred water region in which the food is accordingly also taken up. For example, bottom-dwelling catfish have an underslung mouth with which they can pick up food from the bottom. Fish of the upper water regions (freshwater hatchetfish, guppies) are surface feeders with an upper mouth. Fish in the middle regions have a terminal mouth.

The feed must have swimming, sinking, or floating properties, depending on the species-typical feeding habits of the fish. The aroma of the food is also important because the fish are guided by their sensitive olfactory organs when finding food. Vitakraft ornamental fish food takes into account the different requirements of the respective aquarium inhabitants through its special composition.

The building blocks of nutrition

• Fats are the main source of energy and are therefore also necessary for building up energy reserves. Among other things, Vitakraft ornamental fish food contains fish oil in order to provide the fish with essential omega-3 fatty acids.
• Carbohydrates can also be used as an energy source by some fish. Biochemically, carbohydrates include fibre (roughage), which plays an important role in healthy digestion, especially in herbivorous fish.
• Proteins with their amino acids are the basis of building metabolism and, among other things, enable muscle development, growth, and the development of other tissues. Vitakraft ornamental fish food contains a precisely dosed composition of proteins and thus essential amino acids.
• Vitamins in a quantitatively and qualitatively sophisticated composition support the endogenous protective functions against diseases and are vital for various metabolic processes.
• Vitakraft ornamental fish food contains Immune Active, a specially developed combination of beta glucans, multivitamins, and highly-stable vitamin C.
• Colourants (e.g. astaxanthin) are needed by fish for species-specific colouration, which fulfils important behavioural functions. In addition to intra-species communication, the intense colouration of ornamental fish is also pleasing to look at.

Feeding tips

• It is best to feed small amounts once or several times a day – no more than the fish can consume within a few minutes.
• Ensure a varied diet – this is especially true for community tanks.
• Do not feed directly after maintenance measures (such as water changes or cleaning the glass).

The aquarium should be set up in such a way that you can watch the fish from a comfortable place. As an attractive focal point, the aquarium beautifies any room.

Do not place the aquarium too close to the window. Direct sunlight can promote algae growth and heat the water too much in the summer.

For a larger tank, the load-bearing capacity of the location must also be included in the plans.

The aquarium should be placed on a Styrofoam base or other special support. This will compensate for any minimal unevenness of the storage surface.