FISH - TROPICAL, MARINE , GOLDFISH

An aquarium can transform your room and bring life to almost any dark and dreary corner. With over twenty thousand known species of fish, each with their own habits, colours and shape, the more you discover, the more you will want to know! There are basically three types of aquarium fish - coldwater, tropical and marine.Before you choose think about what you want from your aquarium, learn about the fish available - and don't be afraid to ask your local aquatic retailer for any advice you need.

GOLDFISH

The common goldfish is the most popular pet in the world. Goldfish make the ideal first pet because they are relatively undemanding, hardy, colorful and gentle, and they introduce their owners to the responsibilities of caring for a living creature. Goldfish are fascinating, as they live in a totally different world to our own. However, people can also relate to their goldfish, and it often becomes one of the family, and can even live to see a future generation of that family, as with proper care the fish can live for 30 years. Every goldfish is an individual with its own characteristics, who can recognise its owner and will often rise to be hand-fed. The goldfish is also the one pet that can be safely left for a few days when you go on holiday. It makes no noise, no mess, no smell and with a few simple rules will brighten any home as a living ornament.

CARING FOR YOUR GOLDFISH

Maintaining proper water conditions is the key to successful fishkeeping. Always remember that goldfish have to swim in their own toilet! So flush that toilet regularly - water changes are essential to keep your goldfish happy, healthy and long-lived. Partial water changes are best for the fish - traditionally goldfish bowls are often left until the water is so dirty that the goldfish cannot be seen and is then given a total clear-out, with everything scrubbed clean and the water changed completely. This is traumatic for the fish and the new water gives a chemical shock to the fish - in fact, if untreated tapwater is used it is actually poisonous.

Goldfish (in fact practically all fish) digest food in very much the same way humans do. Just like humans, they excrete the waste, both solid and liquid. While the solid excreta make the water dirty, this is not actually a danger to the fish. In the wild, carp fish often live in water so muddy they cannot see or be seen. The liquid excreta are the danger. Equivalent to our urine, the fish excretes ammonia (as a soluble compound called ammonium), which is invisible. It can poison the fish at only a few parts per million concentration, and is in fact deadly. Even traces will irritate the fish, making it scratch (called 'flashing' and often mistaken for a parasite problem). This chemical also irritates the gills (where the fish breathes), and as a result a protective mucous forms. This reduces the uptake of oxygen and the fish may be seen gasping at the surface trying to get extra air, while the tank water may look perfectly clean and clear.

In mature water, certain types of bacteria can convert the ammonia produced by the fish into another compound called nitrite. This is equally poisonous and also invisible.back to top

The level of nitrite can be easily measured with a test kit from your aquarium shop, and since this also reflects the presence of ammonia, the 'nitrite test' is a good indication of water quality. The ideal is a zero reading at all times. Other bacteria in a mature aquarium convert nitrite to nitrate. This compound is safe (except at very high levels) and is actually used by the plants as a fertilizer.

These so called nitrifying bacteria live on surfaces, so passing the water over a filter medium is a good way to make the reaction occur. This is the basis of 'biological filtration' where a filter pump continuously moves the tank water through filtering material.

Note that the filter is meant to sweeten the water by removing ammonia and nitrite, and is not a system designed to polish the water by simple mechanical filtration. A good filter will indeed give clear water by the filtering action, but it is the biological filtration that is so important for the fish’s health and well-being.

SETTING UP YOUR TANK

When you are setting up your aquarium, you should think about choosing the right location, getting the proper equipment, preparing the water, making best use of plants and, of course, introducing the fish to the tank.

Choosing the Right Location

Choosing the right location for your aquarium is important. You should position your tank near to a mains power socket to ensure easy electrical supply for the lamp and air-pump. It is also best to keep your tank away from strong sunlight, as this can encourage bacterial growth, which can spoil the appearance of your aquarium.

A tank of water is heavy. If you are using a tank without a specially manufactured stand, make sure the surface you choose is strong and flat. It is also advisable to put a piece of expanded polystyrene (e.g. ceiling tiles) beneath the tank to even out any slight irregularities in the surface. And, look for a spot that would benefit from the attraction - don't hide your creation! back to top

Choose a place where it will be seen - even from both sides, for example by using it as a room divider.

The Equipment You Will Need

The hood should have a 'condensation tray' below the light to prevent condensation reaching the lighting unit. The basic equipment you will need (after the tank) comprises a filter and air-pump. The filter is needed to clean the water. Waste solids, such as excreta and uneaten food, must be filtered from the water or they will pollute the aquarium.

There are four basic kinds of filtration:

Internal filtration as the name suggests these filters fit inside the aquarium. Water is drawn in through the bottom of the filter and through filter media - usually sponge - by an electric pump. It is then pumped back into the main water via the outlet or an attached spray bar. Internal filters are ideal for all sizes of tanks.

Undergravel filtration Here the gravel itself is the filter medium. A special undergravel filtration plate is placed on the bottom of the tank with an upright pipe fixed to one corner. The filtration plate is then covered with about 3 inches (8 cm) of gravel. A submersible electric pump, known as a powerhead, pumps water up the tube drawing it through the gravel. The gravel filters the water as it passes through. This system can also be operated by pumping air from an air-pump into the uplift tube.

Reverse flow filtration: This system combines the benefits of both internal filtration and undergravel filtration. A separate internal filter is connected to the uplift tube on an undergravel filtration system. The water is filtered by the first filter before being pumped down the uplift tube and filtered again by the gravel.

External filtration: External filters stand outside the tank. The water is drawn from the aquarium and filtered through one or more filtration media before being pumped back into the aquarium. An air-pump puts additional oxygen into the water.

Fish need to breathe and the water therefore needs to be oxygen-rich. This happens naturally in rivers and lakes, in your aquarium you can help improve the ongoing supply of oxygen with an air-pump. More importantly, the rising bubbles create movement, which circulates the oxygen-rich water at the surface around to the rest of the tank, also increasing the oxygen in the water. This is much more effective and attractive if an airstone is used. Your local aquatic retailer will be able to advise you on the best equipment for your circumstances.
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Preparing the Water

Put the gravel and rocks into the aquarium before adding the water. Rinse all gravel before use in clean water. This is very important as dirty gravel will result in cloudy water, which is difficult to clear. Boil any rocks or bog-wood, before use. If the items are too big to boil then 'scald' them by pouring boiling water over them, taking great care not to splash yourself or any others nearby.

While ordinary tap water can be used, it must first be treated to remove chlorine before fish can be added. The first step in this process is to neutralise the chlorine in the water by adding a neutraliser called a "dechlorinator".

Fish need an environment which contains the right amounts of certain ‘healthy’ bacteria, which help to break down waste, in order to stay healthy. This increase in useful bacteria is called 'maturing'. This maturing process can be speeded up by leaving the air-pump running and adding two or three crumpled flakes of fish food each day to 'feed' the bacteria.

Once this has been done, it should be safe to introduce the fish after14 days. You should carry out a partial water change every 2 to 3 weeks. This means siphoning 20% to 30% of the water out of the tank (you don't need to remove the fish) and replacing it with new water. The new water can be tap water, which has previously been dechlorinated. Altogether, it takes about 2 weeks from first filling the tank, to the water being in the right condition to be able to put your fish safely into the aquarium. back to top

Testing the Water

There are two main potential problems which can occur in aquarium water, which are the build-up of nitrite and an imbalance in pH, resulting in the water becoming acidic. If left unattended both can stress the fish and therefore lower their resistance to disease. Both are easily monitored and controlled with water test or treatment kits. Your aquarian retailer will be able to advice you on these. Plants Aquatic plants can be used to create an underwater garden.

Common goldfish have a tendency to eat plants, and you may want to use artificial plastic plants, which will last. In this respect, fancy goldfish tend to be much better behaved. It is possible to buy tropical aquatic plants which will thrive in room temperature conditions, however, if the room gets very cold, it is best to use coldwater plants such as Elodea. The best base for plants (and the fish) is river sand. A good source of sand is that sold for children's play pits. A 10kg bag provides more than enough for a 90 centimetre aquarium.

The use of sand is not recommended with under-gravel filters, as they may become blocked. back to top

Introducing Fish to Your Tank

Fish need living space, so be careful not to overstock your tank. As a general rule allow 75 square centimetres of surface water area for each centimetre of coldwater fish, (head to tail, but not including the tail fin). Ideally, you should allow 10 litres of water per goldfish.

Check that your fish have been properly quarantined before sale. Disease often takes a few weeks to show and a fish not quarantined can easily introduce diseases, which may infect all your fish. It is also better to add your fish gradually, starting off with only two or three fish, building up over the months as your tank matures.

Buy your fish locally if possible - long journeys can easily stress your fish. Before you let the fish free, float the opened plastic bag on the surface of the tank for about 20 minutes to equalise the water temperature and reduce the stress on the fish. Fish, which have just been introduced into a new tank may be nervous and hide. In this case, it is best to switch off the tank lights and leave them for a few hours to get used to their new surroundings. After that time you can give them a few fish flakes.

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MARINE FISH

This type of fish keeping is for the more experienced aquarist, although marine fish keeping is not difficult once the initial setting-up has been done. The initial start-up is called the 'nitrite crisis', which must be created and passed through before adding any marine fish or invertebrates to the tank. It is important to know about specific gravity, pH and how to measure ammonia, nitrite and nitrate levels, as well as choosing the right thermostatic heating, filtration, lighting, etc.

Marine fish for the aquarium are actually coral fish, many of which are easy to keep once the seawater quality is ideal. Corals themselves are more difficult to maintain and their importation is now regulated such that some types are not readily available to the hobbyist. Artificial corals are, however, also available for decorating the marine tank.

SETTING UP YOUR TANK

Choosing Your Tank

Choosing a suitable aquarium is one of the most fundamentally important decisions that need to be made. It is, therefore, well worth spending some time weighing up several possibilities before making the final choice. As with the freshwater hobby, there are two main points to consider, the type of aquarium and its size.

Aquarium Type Plastic and perspex tanks have the advantage of being relatively light and inexpensive. However, there are several disadvantages, such as the discolouring which occurs with age and the ease with which plastic scratches. Angle Iron tanks are potentially lethal, as iron reacts with the salt water and can produce substances which would normally be tolerable in freshwater, but potentially lethal in marine aquaria.

The most popular aquaria today are those made entirely of glass. They come in all shapes and sizes to suit every conceivable need and pocket. Aquarium Size However large an aquarium may be, it is still minute when compared to the natural environment in which fish normally exist. As a consequence of this, there will be a build-up of certain substances and a possible lack of others which can cause serious problems if the maintenance routine is inadequate. back to top

One factor that will help or hinder the development of an adequate routine is the size of the aquarium, and the smaller the volume of water present, the more susceptible it is to change. It, therefore, makes sense to go for the largest aquarium possible from the start. The extra expense will more than pay for itself in a short time, simply by the number of expensive problems that will be avoided. A 90 x 38 x 30cm tank should be considered the minimum by anyone who has not kept marine fish before.

Aquarium Cover

Two points are worth bearing in mind. First, it is essential that there are no exposed metal parts. If there are they will react with the salt water and will cause, at best, distress to the fish and, at worst, their death. This can be avoided by painting the exposed metal with a non-toxic gloss paint. The second point concerns evaporation and splashing of water. Both are unavoidable, particularly since aeration is quite vigorous, and to control this, use a condensation sheet. Condensation sheets can be bought ready-made in plastic.

Water Quality Maintenance of good water quality is an absolute must in marine aquaria. The following are the most significant aspects of water chemistry that need to be appreciated BEFORE a start in the marine hobby is made. Specific Gravity (SG), Salts and Trace Elements Salt water, as the name implies, carries a number of chemicals dissolved in pure water. These chemicals make the water heavier, or denser. The way in which this compares to the weight of pure water at 4°C that gives the figure referred to as specific gravity (SG) (also known as relative density). In the marine aquarium, a SG between 1.020 and 1.023 is suitable for most species. This value is achieved by dissolving balanced prepared aquarium salt mixes in the recommended amounts in water and measuring the SG with a hydrometer.

Hydrometers are calibrated to give readings at the range of temperatures at which most tropical species are kept, i.e. 24°C - 26°C. Many of the available salt mixes also contain all the essential trace elements, which fish and other organisms require. Ammonia, Nitrites and Nitrates These three chemicals all contain nitrogen. It is important to keep the nitrogen cycle under control, with nitrite readings at (or near) zero and ammonia readings always at zero. This can be achieved in a numbers of ways, most of which involve some form of filtration. pH - Acidity and Alkalinity Pure water is said to be neutral and is given a pH value of 7.

Lower figures represents progressively higher degrees of acidity and higher figures represent higher degrees of alkalinity. The pH range for tropical marine tanks should be between 8.0 and 8.3, i.e. alkaline. This can be measured by means of reliable, inexpensive test kits. Certain types of substrate will help maintain the pH above 8.0. Aeration and Filtration Aeration and filtration systems vary in design, but they all aim at oxygenating the water and reducing or eliminating toxic wastes from it. Two types of filtration are required, which are a mechanical filter to remove the debris and a biological system to remove the rest. Many systems do both and aerate the water at the same time.

Different types of filter include box filters, undergravel filters, reverse filtration, trickle filtration and combined filtration system. A protein skimmer is also useful for removing excess dissolved organic matter in marine aquaria. Your local retailer will be able to advise you on the best system for your tank. back to top

Temperature Control

Most commonly available marine fish are best kept at water temperatures between 24°C –26°C. The easiest method of heating an aquarium is by means of a combined heater / thermostat. When calculating the heating requirement for an aquarium, allowances should be made for major declines in external room temperature. In order to allow for sufficient reserve power, it is best to choose a heater with twice the wattage that would normally be required. Discuss your requirements with your local aquatic retailer.

Aquarium Lighting

The two main forms of marine lighting are Tungsten bulbs and fluorescent lights. Tungsten bulbs are cost effective, but get hot and do not enhance the appearance of the fish as much as some fluorescent tubes will do. They do, however produce light relatively rich in ‘red’ wavelengths, which are beneficial to the growth of green seaweeds. Special lighting (e.g. metal halides) is available for mini-reef systems. back to top

Filling the Aquarium

Synthetic salt mixes carry full instructions on mixing and these must be followed very carefully to avoid problems later on. Before placing any water in the aquarium, all filters, gravel, etc. must be in place, but no electrical equipment switched on. Now, half fill the aquarium with water, put in the complete salt complement and then fill completely. At this point install the heater and switch on along with the filtration and aeration. Leave the aquarium running for 24hours. Now check the specific gravity (SG) and adjust accordingly.

Although your tank may now appear to be balanced, it needs to mature for two weeks. Over this time the nitrite level should first increase beyond tolerance levels and then drop to zero. At this point, assuming the pH is correct, fish may be introduced. back to top

MAINTENANCE

Every aquarist soon develops a maintenance regime based on aquarium size, type of fish and many other considerations. Every maintenance programme should, however, include the following points on a regular basis: Daily Check on temperature, health of your fish, feed your fish twice daily, and switch tank lights off ten minutes before room lights. Ensure the filters and aerators are working correctly.

Weekly or Every 2 Weeks Check specific gravity (SG), pH and nitrite levels; check heater/thermostats for possible leakage and add water if necessary. Every 3 to 4 Weeks Clean filters and cover glass, scrape algae off the sides of the tank if necessary; check aerator and lighting equipment, especially for crustations of salt, which can creep along wires and tubes. Every 4 to 6 Weeks Gently stir topmost layer of coral sand or gravel; allow mulm to settle and then remove with a siphon tube; carry out a 20 - 25% water change; prepare the new water 24 hours in advance, aerate it vigorously, and check all parameters before adding it to the main tank.

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TROPICAL FRESHWATER FISH

Tropical freshwater fish originate in the freshwater rivers and lakes in the warmer parts of the world, particularly South America, Central Africa and Asia. There are literally thousands of species of these fish, with new ones being discovered regularly. Tropical freshwater fish must be kept in water heated to 25°C - 28°C (77°F - 82°F). A large variety of beautiful tropical fish are available, which makes them an excellent choice for your first aquarium. Many species, such as Guppies, Swordtails and Angelfish live together well - these are known as 'community fish'. In a community tank you might wish to have fish, which live and feed at all levels from top feeders such as Mollies, mid water feeders such as Barbs, and fish, which live and feed on the bottom of the tank, such as Catfish.

SETTING UP A TROPICAL TANK

When you are setting up your tropical tank you should think about choosing the right location, using the proper equipment, preparing and testing the water, using plants and light and, of course, introducing your fish to the tank.

Choosing the Right Location

If you are using a tank without a specially manufactured stand, make sure the surface you choose is strong and flat. It is also advisable to put a piece of expanded polystyrene (e.g. ceiling tiles) beneath the tank to even out any slight irregularities in the surface. And, look for a spot that would benefit from the attraction - don't hide your creation! back to top

Choose a place where it will be seen - even from both sides, for example by using it as a room divider.

The Equipment You Will Need

It is recommended that you purchase a good quality glass aquarium with hood. The hood should have a 'condensation tray' below the light to prevent condensation reaching the lighting unit. The basic equipment you will need (after the tank) comprises a filter and air-pump. The filter is needed to clean the water. Waste solids, such as excreta and uneaten food, must be filtered from the water or they will pollute the aquarium.

There are four basic kinds of filtration:

Internal filtration As the name suggests these filters fit inside the aquarium. Water is drawn in through the bottom of the filter and through filter media - usually sponge - by an electric pump. It is then pumped back into the main water via the outlet or an attached spray bar. Internal filters are ideal for all sizes of tanks.

Reverse flow filtration :This system combines the benefits of both internal filtration and undergravel filtration. A separate internal filter is connected to the uplift tube on an undergravel filtration system. The water is filtered by the first filter before being pumped down the uplift tube and filtered again by the gravel.

External filtration: External filters stand outside the tank. The water is drawn from the aquarium and filtered through one or more filtration media before being pumped back into the aquarium. An air-pump puts additional oxygen into the water.

Your local aquatic retailer will be able to advise you on the best equipment for your circumstances. Heating A heater thermostat is used to warm the water. Tropical fish need to be kept in water at about 25°C - 28°C (77°F - 82°F). Make sure that you choose a heater thermostat suitable for the size of your tank. Preparing the Water Put the gravel and rocks into the aquarium before adding the water. Rinse all gravel before use in clean water. This is very important as dirty gravel will result in cloudy water, which is difficult to clear.

Boil any rocks or bog-wood, before use. If the items are too big to boil then 'scald' them by pouring boiling water over them, taking great care not to splash yourself or any others nearby. Whilst ordinary tap water can be used, it must first be treated to remove chlorine before fish can be added. The first step in this process is to neutralise the chlorine in the water by adding a neutraliser called a "dechlorinator".
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Fish need an environment, which contains the right amounts of certain ‘healthy’ bacteria, which help to break down waste, in order to stay healthy. This increase in useful bacteria is called 'maturing'. This maturing process can be speeded up by leaving the air-pump running and adding two or three crumpled flakes of fish food each day to 'feed' the bacteria. Once this has been done, it should be safe to introduce the fish after14 days.

You should carry out a partial water change every 2 to 3 weeks. This means siphoning 20% to 30% of the water out of the tank (you don't need to remove the fish) and replacing it with new water. The new water can be tap water, which has previously been dechlorinated. The new water should be warmed to about to about 25°C (77°F) and poured carefully into the tank, in order to minimise stress to the fish.

Altogether, it takes about 2 weeks from first filling the tank, to the water being in the right condition to be able to put your fish safely into the aquarium. Plants One of the common problems are poorly growing plants, which eventually die. The secret is to choose plants with good roots. In the wild the roots are deep in still mud, but in the aquarium plants are often expected to thrive in gravel. It is important to buy plants with good bushy roots, in fact, this is more important than looking out for nice green leaves (as the leaves will quite easily grow back after trimming). The roots must be deep in soil or at least protected with material such as rockwool so they are not damaged when transplanting.

Pre-potted plants are available, alternatively you can pot your own using small seed pots filled with loam and topped with gravel to prevent the soil from fouling the water. River sand is better than gravel for the planted aquarium, and should be deep enough to cover the pre-potted plants. An ideal source is children’s play sand, which just needs to be rinsed well before use. back to top

Choose the well-tried and tested aquatic plants such as Vallisneria, Egeria, Elodea, Cabomba, Cryptocoryne, Echinodorous, Hygrophila, Ludwigia, Myriophyllum and Amazon Swords. Plant them in singles and in groups of threes or fives. It is advisable to plant the aquarium while it is only three quarters full of water. This does not only make the job much easier, but you can also see the visual effect of the aquascaping, and you won’t get too wet! Lighting Green plants use photosynthesis to grow, which requires a certain level of light. Hence the same light levels are needed whether the aquarium has few or many plants. However, if you have a very few plants, light can encourage the growth of algae, which can destroy plants.

Fluorescent tubes are a popular choice because their running costs are low and they are cooler than light bulbs. The following are recommended minimum light levels: Length of Tank Tungsten bulb Fluorescent Lights 45 cm (18") 1 x 40w 1 x 8w (12") 60 cm (24") 2 x 40w 2 x 15w (18") 76 cm (30") 3 x 40w 2 x 20w (24") 90 cm (36") 4 x 60w 2 x 20w (24") 122 cm (48") 4 x 60w 3 x 30w (36") Plants need a daily rhythm of light and dark just like animals, so lights should be switched on for 10 to12 hours, and off for 12 to 14 hours at a fixed time every day. A timer is useful for this routine.

Testing the Water

Introducing Fish to Your Tank

Fish need living space, so be careful not to overstock your tank. As a general rule allow 75 square centimetres of surface water area for each centimetre of tropical water fish, (head to tail, but not including the tail fin).

Fish, which have just been introduced into a new tank may be nervous and hide. In this case, it is best to switch off the tank lights and leave them for a few hours to get used to their new surroundings. After that time you can give them a few fish flakes.

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