1. Aquaria Construction, Design and Management (a brief
overview).
Famous-cole A.O, Animashaun S.O, Shittu A.J, Fasasi A.O, Oyedele M.O
Department of Fisheries, Faculty of Science, Lagos state University, Nigeria
CHAPTER ONE
1.0 INTRODUCTION
Aquarium is a receptacle for maintaining aquatic organisms, either freshwater or marine, or a
facility in which a collection of aquatic organisms is displayed or studied.
Fig 1: a typical aquarium

2. 1.1 DESIGN AND ARCHITECTURE
1.1.1 Defining requirements
Building design should take into account a number of points. There should be a rather large
lobby for receiving the visitors; it is a usual practice for public aquaria to receive groups of
people: school classes, groups of tourists, visits from universities and visits organized by
societies. The entry to the aquarium display should be slightly delayed for the adaptation of the
visitors to the dim light of the surroundings. Information referring to the exhibits and aquarium
activities in the form of posters or power point projections can keep the visitors occupied while
they proceed slowly to the tank display area. The whole way should be flat for safety reasons.
The display area should be viewed on the “one way” pattern and the exit should lead, if
possible, to a small museum or exhibition place providing additional information mainly
through preserved specimens and panels, posters and computer programs. This supplementary
information will also prolong the time spent in the aquarium building. Eventually the visit
should lead to an aquarium shop near the exit. Visitors should not have any access to aquarium
installation, laboratories or other ancillary facilities unless a specific visit has been arranged,
programmed thoroughly and all safety measures have been taken.
Space requirements for pumping facilities, the master tank, the control room, laboratories,
storage place, tanks for fish quarantines and tanks for the reserve fish stock have to be taken
into account.
1.1.2 SITE SELECTION
It is an advantage if a seafront area is chosen. The selection parameters are a trade-off between
high quality environmental conditions and vicinity to a town that will be the potential source
of visitors and academic activities. The most important factors to the technical aspects of the
aquarium as far as the marine environment is concerned are:
(a) High water quality is absolutely necessary for the tank supply
(b) Wild populations of desired species in the area, form a good source of living organisms.
Although aquaria tend to import living organisms from all over the world, small aquaria largely
rely on the local marine ecosystem
(c) Endemic diseases and parasites
(d) Microbiological populations i.e. possible pathogens and
(e) Coastal seawater circulation and wave regime: related to water renewal as well as to
possible re-suspension of the sediment in the water abstraction area.

3. The most important factors concerning the accessibility of the site area are:
(a) Distance from the nearest city
(b) Regular public transport
(c) Size of school population in the area
(d) Academic and research institutions in the area
(e) National parks, conservation areas, ongoing plans in the area on conservation and
biodiversity issues.
CHAPTER TWO
2.0. AQUARIUM CONSTRUCTION
2.0.1. Construction Materials
Glass is probably the safest basic material, although polyethylene, polypropylene, acrylic
plastics (Plexiglas), and fluorocarbon plastics are normally nontoxic. Fibre glass has been
widely used and is nontoxic if properly prepared. Adhesives for sealing include epoxy resins,
polyvinyl chloride, silicone rubber (except for certain coloured preparations), and neoprene.
Metals are not usually used, especially in seawater, which is highly corrosive. Stainless steel,
however, has a low toxicity, and is often used, especially in freshwater systems.
A small aquarium can be constructed entirely of glass and without supporting frames by using
silicone rubber as an adhesive. Fibre glass is probably the most practical supporting material
for all but the largest tanks since it is lightweight, strong, does not deteriorate, and is easily
fabricated into any shape. Wood, though widely used, is subject to rot and boring organisms
and thus must be protected. Reinforced concrete, including special mixes for seawater, is the
principal supporting material used in the construction of large aquariums.

4. In modern aquariums tanks of a variety of sizes and shapes are often grouped together in order
to avoid the “boxes of fish” look that characterizes some of the older, formal aquariums. Dry
dioramas at the rear of the tank create the illusion of distance; the tank habitat can be a natural
one or one in which fibre glass has been impregnated or painted to duplicate almost any
environment. Modern aquariums attempt to illustrate the natural environment of the specimens
displayed.
Polished plate glass, fully tempered polished plate glass, and Plexiglas are the most commonly
used glazing materials. Polished plate glass is usually used only in small aquariums because it
breaks into large pieces when it fails. One generally accepted practice is to glaze large tanks
with two or three layers of tempered glass so that if breakage occurs it is confined to one layer.
Although Plexiglas is easily scratched, it can be re-polished.
A small aquarium can be constructed entirely of glass and without supporting frames by using
silicone rubber as an adhesive. Fibre glass is probably the most practical supporting material
for all but the largest tanks since it is lightweight, strong, does not deteriorate, and is easily
fabricated into any shape. Wood, though widely used, is subject to rot and boring organisms
and thus must be protected. Reinforced concrete, including special mixes for seawater, is the
principal supporting material used in the construction of large aquariums.
In modern aquariums tanks of a variety of sizes and shapes are often grouped together in order
to avoid the “boxes of fish” look that characterizes some of the older, formal aquariums. Dry
dioramas at the rear of the tank create the illusion of distance; the tank habitat can be a natural
one or one in which fibre glass has been impregnated or painted to duplicate almost any
environment. Modern aquariums attempt to illustrate the natural environment of the specimens
displayed.
Polished plate glass, fully tempered polished plate glass, and Plexiglas are the most commonly
used glazing materials. Polished plate glass is usually used only in small aquariums because it
breaks into large pieces when it fails. One generally accepted practice is to glaze large tanks
with two or three layers of tempered glass so that if breakage occurs it is confined to one layer.
Although Plexiglas is easily scratched, it can be re-polished.
Accessories for individual tanks normally include filters, air pumps, lights, and electric
thermostatically controlled immersion heaters, or perhaps alternately, some means of chilling
the water. In aquarium buildings the tanks are usually grouped so that they have a common

5. filter and method of temperature control. Water sterilizers may be included. Plumbing in large
aquariums with multiple systems is sometimes complex, involving a variety of automatic
controls and water-quality monitoring systems. Because of its cost and fragility, glass plumbing
(e.g., for aeration or circulation of water within an aquarium) is used only in cases in which
low toxicity is essential. Unplasticized polyvinyl chloride pipe is widely used. Fibre-glass pipe
and epoxy-lined asbestos pipe are sometimes used, but lead and hard rubber pipe are obsolete.
In seawater systems the growth of fouling organisms such as mussels and barnacles are avoided
by providing the system with duplicate pipes and alternating their use on a weekly basis. When
a line is dry, the few organisms present die and are flushed out when the line is again put into
service.
Non-metallic or plastic-lined pumps are better than metal ones in terms of toxicity, but stainless
steel is often satisfactory. Airlift pumps (such as those used in home aquarium sub-sand filters)
move large volumes of water when the lift pipes are of sufficient diameter.
Generally, the most effective illumination is by incandescent lamps placed above the front
glass. Fluorescent lights provide even illumination but may over illuminate the tank walls;
coloured lights accentuate natural colours; and mercury-vapour lamps encourage maximum
growth of marine plants.
Fig 2: Silicon and glass materials
Glass Aquarium Pros
 Cheaper than Acrylic Tanks most of the time
 Much harder to scratch but it still can happen
 Tanks are usually industry standard sizes, making lids and such easy to purchase
 Easier to clean because there is less need to worry about scratching

6. Glass Aquarium Cons
 Heavy – A glass tank is much heavier than the same size Acrylic tank, making it harder
to move
 Glass can be drilled for bulkhead fittings but it’s much more nerve racking than drilling
Acrylic
 Not as efficient at holding in temperature compared to Acrylic
 Scratches cannot be fixed
 Harder to fix if you chip or crack a panel, since replacement is usually needed unless it
is a small chip
 Not quite as clear as Acrylic
Acrylic Tanks are great, they are light and easy to move. As well as easy to fix and repair.
However they do have some downfalls as well. I tend to prefer them myself, especially in larger
tanks because of the weight issue alone. I also like the flexibility of Acrylic, it can be cut and
modified much easier. However it also scratches much easier too, this is the one thing many
people prefer glass. I’ll leave it up to you.
Acrylic Aquarium Pros
 Super clear (Unless you get a hazy used one but it can be buffed and polished)
 Super lightweight compared to glass
 Easier to drill for bulkhead fittings
 Can be refinished, re-polished and repaired if they break
 Less likely to break from impact, Acrylic has a bit more give than glass. I’ve dropped
a 50lb lighted hood down on a tank full of water and it didn’t break. The impact was
tremendous.
Acrylic Aquarium Cons
 Scratches super easy
 Harder to clean because you have to be so careful not to scratch it
 Expense – Acrylic tanks are typically more expensive per gallon

7.  Some are not standard sizes, making it more difficult to find lids or lights to fit perfectly
SHAPE AND POSITION
Originally, there were only the rectangular aquariums but today there are unlimited numbers
of possible shapes: square, triangle, column-shaped, pyramid shaped, etc. and not every fish
can be kept in every type of aquarium.
The position where the aquarium is to be kept is of importance as certain fish species will not
tolerate the slamming of doors. The aquarium should be kept in a decorative and safe
position, away from direct sunlight to avoid algal bloom.
2.1 PROCEDURE FOR CONSTRUCTING AN AQUARIA TANK
 Put your prepared glass pieces on a flat surface
 Collect one of the glass panes for the base and set it on a flat table and the other four
(4) pieces place adjacent at sides
 Apply a bead of the adhesive round the edges of the bottom panel and at two side edges
of the front and back panel with the aid of the hanger.
 Run a continuous 1/4 inch bead with no gaps or bubbles. Install the back glass panel on
the bottom and the side panels are fixed inside the back and front panels.
 When all the panels have been set in place the silicone is smoothed out with the tip of
your finger and the panel supported at the corners with a masking tape. Thus, the
aquarium is constructed such that the two end pieces of glass fit inside of the back and
front panes and the front, back and two side panes set on top of the bottom base pane
of glass. The best bonding results are achieved by applying only as much silicone as
you can within 3 to 5 minutes, because after this, the silicone tends to skin over and
won’t bond well to the glass.
2.2 STEPS IN INSTALLING THE AQUARIUM TANK
 After testing for leakages, wipe out the tank using a clean, damp cloth and place it on
it stand
 Cover the bottom with a layer of clean sand (about 2.5 cm thick)
 Add the aquarium gravel and smooth it out with the air wall tubes and hose covered

8.  Add various rocks on the bottom which enhance the aquarium and also give fish a place
to hide
 Add the water by placing a small bowl on the gravel and pour the water into the bowl.
Let it run over the sides, filling the tank without disturbing the gravel or rocks.
 When the aquarium is full. Test the water with pH meter before adding live aquarium
plants and fishes
 Float the fishes, which are still in oxygenated water-bags or containers from the store
into the tanks
 Put the cover in place to prevent the fish from jumping
FIG 3: wooden frame for aquarium construction

9. Fig 4: setting of the wooden frame for the construction
Fig 5: bottom plan of the aquarium

10. Fig 6: Coating of the glass
Fig 7: A complete aquarium

11. CHAPTER THREE
3.0 AQUARIUM MAINTENANCE
An aquarium is basically the resemblance of an underwater ecosystem. In order to maintain
similar conditions to the natural environment and habitat of the species that live in the tank, it
is necessary to maintain constant water conditions as well as optimal water quality levels
specifically required by each organism in the aquarium tank. To reach these conditions, it is
essential to be familiar with the right type of equipment in order to supply the appropriate
environmental conditions that each species requires. Whether you choose to have a saltwater
tank or a freshwater tank, you will need to take care and protect your system and equipment,
however, as salt is a corrosive agent, a freshwater tank may be more recommended for
beginners because it may be easier to maintain. Management practices in an aquarium include:
3.0.1 CHANGING THE WATER
A key part of aquarium maintenance is the water change, which should be performed about on
time. In most cases, 10-15% of the tank volume is sufficient. A good method is to replace the
water extracted while vacuuming the gravel, which will eliminate uneaten foods and other
residues that settle on the substrate. It is highly recommended to check the water parameters of
both the tank and replacement water.
3.0.2 FILTRATION
Both freshwater and marine aquaria need aquarium filters. Physical and soluble chemical waste
can accumulate in aquaria and aquarium filters help remove these wastes. Most fish
accustomed to their natural environments will not be able to survive in aquaria without the help
of aquarium filters because they are not used to the small water volume. In a small, confined
volume of water, there is no waste dilution system that happens in the natural aquatic
environment. Whether you have a large tank or a small one, you will still need a filtration
system to keep the fish healthy and alive. Toxic ammonia can be a serious problem and you
cannot keep changing the water as often as it needs to be changed. Water in aquaria has a
tendency to become contaminated due to uneaten plant food and waste from excrement. The
health of aquaria can be in jeopardy if contamination level is too high. For healthy aquaria
maintenance, Filtration procedures are employed which help remove contamination.
The three categories of filtration

12. There are three types of filtration that are necessary for the health of any aquarium:
 Mechanical
 Chemical
 Biological
Before choosing a filtration system, it is important to understand all three, and how they will
benefit your aquarium.
Mechanical Filtration
Mechanical filtration is the straining of solid waste particles from the aquarium water. To limit
the production of ammonia in aquarium water, you need to limit the filter waste products before
they get a chance to decay. Decay is not only very dangerous because it causes high levels of
ammonia in the fish water but it is also something that gives your aquaria a bad appearance.
Fish gills can also produce ammonia as a waste matter, as do fish excretions. Fish food rotting
away can have the same effect. Mechanical filters are designed in a way that they will not
remove microscopic bacteria and algae and they also won't remove any solids trapped by gravel
or your decorations. They have no effect on dissolved ammonia either. Mechanical filtration
media include bonded floss media which have the largest openings, loose floss media, as well
as paper cartridges which have the smallest openings and clean sponges.
To certain degrees these items are reusable. Finer particles may be easier to catch with small
openings of a filter media but they can also become clogged. The idea is to have a mechanical
filter that traps enough solids to keep the water clear without frequent plugging. A large filter
area clogs slower than a small filter. Smaller and smaller particles are trapped when filter media
gets dirty until it can no longer pass water.
Fig 8: filter foam

13. Biological Filtration
To build a successful aquarium you need nitrogen cycle management and to do that you need
to foster essential bacteria growth. Ammonia produced as a result of excretion and
decomposition of organic matter can become toxic and fish will not be able to survive in it.
Ammonia needs to be first broken down into nitrites which are less toxic and then into nitrates.
This breaking down takes places when bacterial processes oxidize ammonia. The idea is to
produce nitrates which can be taken up by plants thriving in the environment as fertilizer but
the problem is that most aquarium environments are not replicas of natural environments.
You may have more fish producing ammonia than you have bacteria and plants. The small
volume of a fish aquarium actually has higher ammonia levels than anywhere else.
Bacteria required for biological breakdown of ammonia grow on surfaces within the aquarium.
Using a biological filter in such a situation can be very helpful. This filter uses a chemically
inert porous sponge so bacteria can develop on the massive surface area. A biological filter is
necessary when you have a large quantity of fish.
Biological filters increase the capacity of the bacteria colony and increase the available oxygen
dissolved in the water.
Fig 9: Bio balls
Chemical Filtration
The removal of dissolved wastes from aquarium water is known as chemical filtration. At the
molecular level, Polar and Non-polar dissolved wastes can exist in aquaria. There are several
methods through which these wastes can be removed. The process of chemical filtration can
be achieved by filtering the aquarium water through gas activated carbon or through protein
skimming. Activated carbon works for non-polar wastes while protein skimming is ideal for
polar wastes.
When coal is warmed in the presence of steam at very high temperatures the carbon develops
huge numbers of tiny pores which is known as Granular activated carbon (GAC). GAC causes

14. the non-polar wastes to be trapped by processes of adsorption and ion exchange. Through the
process known as molecular sieving, GAC also removes heavy metals and organic molecules
in water. These molecules give the water smells and colours you don't need in an aquarium
setting.
This form of macro porous activated carbon is not as dense as GACs used to filter air and that
is why they float in water. Phosphate leaching from GACs is a problem which can become a
hurdle for reef aquaria and that is why activated carbon should only be bought from reliable
companies. These manufacturers give the GACs an acid wash which to minimize ash content
to attain lower phosphate leaching levels. These GACs will also keep the aquarium water safe
from pH shifts of any kind. Pre-soaking your activated carbon for a few weeks before use can
further lower the risk of phosphate leaching.
In order to remove specific chemicals, special chemical filtration media have been developed
like zeolite clay removes ammonia from aquarium water but it will disrupt or delay the
establishment of natural biological filtration.
This is why this particular filtration media should be used only for short periods of time and is
not a long term solution.
For saltwater aquaria like reef, protein skimmers work best. The way it works is by removing
dissolved organic wastes before decomposition takes place. The polar nature of the organic
molecules will cause air bubbles and the foam that forms as a result can be skimmed off.
Fig 10: Activated carbon
3.0.3 VACUUMING
A gravel vacuum is a piece of aquarium equipment. It is a rigid, plastic tube, generally about
2" in diameter which attaches to one end of a siphon tube to allow you to clean the debris from
part of the aquarium gravel with each of your weekly 10-15% water changes.
Once you have your siphon started, you will need to place the end of the gravel vacuum into
the gravel. With your finger or thumb blocking the bucket end of the siphon, gently slide the

15. vacuum end of the gravel vacuum into the gravel. Keep the tube moving in a straight line, and
do not move the vacuum back and forth or up and down (this will just make a mess).
Once the end of the gravel vacuum is in the gravel as far as it will reasonably go, release your
finger or thumb from the bucket end of the tube. Water should start flowing through the tube,
and the gravel in the tube should start shaking, bouncing, and churning. Debris should be
flowing down the siphon and into the bucket.
Once the water coming through the gravel is mostly clear, stop the flow of the siphon by placing
your finger or thumb over the bucket end of the siphon tube. This should stop the flow of water
and allow the gravel to settle.
3.0.4 ALGAE REMOVAL
The appearance and growth of algae in an aquarium is not necessarily bad. In fact, it is the
natural order of things. It shows that your aquarium is well balanced and healthy. Only when
the algae are allowed to grow out of control and cover everything is it a problem. Left
unchecked, it can cover the glass - in colours ranging from black to bright green in freshwater,
or even pink, purple, or burgundy in saltwater - making viewing your beautiful inhabitants
impossible. It can also quickly cover the decorations, diminishing the appeal of the entire
environment. Algae keeps things looking natural and provides a food source for fish and
microorganisms. Thus, your goal should not be to eliminate all algae. Instead, it should be to
manage its growth to keep the population at a desirable level.
Many aquarists who encounter hair or other tough algae treat the symptoms, not the problem.
For example, they may bleach all their decorations and gravel and then treat the water with a
de-chlorinator, placing the health of their fish at risk, only to discover the algae making a fast
comeback within days. Knowing what factors contribute to algae growth, and your control
options, will help you keep a healthy, well-balanced aquarium.
3.0.5 FEEDING
Fish, like any other organism, need a supply of calories to sustain their metabolism. Properly
feeding your fish helps them to stay healthy and is helpful in maintaining your aquarium. It is
important to know the types of foods your fish need and how much food they need, which
differs from species to species. In most cases, fish only need to be fed once a day and you only
need to feed a small amount. Your fish should be able to get enough nutrients from the food
they can consume in less than two minutes, as long as the food provides for their nutritional
needs. Food that stays in your tank longer than that can get caught in your gravel, decorations,

16. or filter and will begin to decay, contributing to poor water quality. This poor water quality
will increase disease susceptibility and filter maintenance. It could also increase the need for
water changes, which in turn stress the filtration system and the fish, again increasing disease
susceptibility. Small, regular feedings provide fish with the nutrients they need and keep your
tank cleaner than large or more frequent feedings.
Over feeding can also contribute to algae growth, which can be unsightly, remove vital oxygen
from the water, and increase your tank maintenance chores.
Most fish, like most cold blooded vertebrates, are primarily carnivorous, consuming mostly
insects, insect larvae, worms, grubs, various shrimps and similar animals, and smaller fish,
some even consuming small amphibians, reptiles, birds and mammals in the wild. However,
almost all fish also graze on live plants, and there are very few that do not consume at least
some algae. So, you can see that most fish are really omnivorous and need to get foods that
contain both animal and vegetable matter to remain healthy.
The foods are engineered to provide a complete and balanced diet for your fish and are available
in a variety of forms: floating pellets, sinking pellets, granules, tablets, and flakes.
 Flakes are the most common type of processed foods, and are available in a very wide
variety. Some flakes are engineered to provide the nutritional requirements of specific
varieties or species of fish, and others are designed to counter nutritional imbalances,
while still others are balanced to enhance colour or growth or to encourage spawning.
 Pellets are available in forms that are denser or lighter than water. This allows the fish
to feed in a more natural way if the right pellet is provided. Some fish prefer to feed off
the bottom of the tank while others prefer to feed off the surface. Like flakes, pelleted
foods are available in many varieties, each with a specific purpose.
 Granules are like very small, hard flakes or tiny pellets. Currently only a limited variety
of fish food granules are available, usually engineered for the general nutritional needs
of small community fish.
 Tablets are really just large flat pellets. Most tablets are of a sinking variety, but there
are some that are engineered to adhere to the side of the aquarium so that you may
observe your fish feeding. Most of the sinking tablets are engineered to provide for the
nutritional needs of scavengers and bottom feeders.

17. 3.1 AQUARIUM MAINTENANCE ROUTINE
The schedule for cleaning your fish tank will depend primarily on:
Tank Placement: The reason the setup is important when it comes to maintenance and cleaning
is that if you place the tank in a location hard to get to, chances are it will not be cleaned on a
regular schedule. Therefore, make sure the placement of the tank is such to give you adequate
room.
Tank Size: Interestingly, a larger tank actually requires less maintenance than a smaller tank.
The reason is that the larger tank has more water volume, meaning the waste excreted by the
fish along with chemicals and other particles are dispersed over a much larger area. Therefore,
if you buy a 10-gallon tank opposed to a 50-gallon tank, you can expect to clean the smaller
one more often.
Filtration System: A filtration system is crucial to keeping the tank clean and the environment
healthy. Many people will use biological filtration, which allows the right amount of "good"
bacteria to grow while maintaining the proper level of Nitrite coupled with a mechanical filter
or chemical filter. The mechanical consists of a box that fits within the tank in which some type
of media is used to filter out waste and other particles. The chemical filter uses chemical media
such as carbon or chemical resins to absorb the waste.
Feeding Habits: One of the most common mistakes made by fish owners is that they feed the
fish too much and too often. When there is excess food in the water, it causes pollution.
3.1.1 DAILY
Fish, just like any other pet, need to be cared for on a daily basis. Although fish do not have
the same level of requirements for daily care, they do need to be looked after on a consistent
basis.
Feeding: Feed the fish, again taking care to feed only as much as what will be eaten
immediately.
Water Temperature: Check the water temperature, keeping in mind temperatures will
fluctuate throughout the day. Therefore, test the water each morning and then again in the
evening. To maintain a healthy tank, you should keep a chart of your findings so you can
identify any problems before they turn out of control.
Equipment Check: Make sure the filter, heater, and lights are working properly
Behaviour Check: Take a few minutes to watch the fish to see if they are swimming normally.
Additionally, look at their skin, looking for any sign of disease.

18. Water Check: Look at the water to ensure it is not cloudy, does not have a foul odour, and
that nothing out of the norm is floating around
3.1.2 WEEKLY
In addition to the daily responsibilities of owning fish, there are certain things that will need to
be done on a weekly basis as well.
Plants: If you keep live plants in your fish tank, be sure any dead leaves are removed and excess
plant growth trimmed.
Algae: Using an algae magnet or scraper, clean off algae from the front glass as well as
decorations.
Water Change: Using a siphon hose, remove large debris from the surface and then with a
bucket nearby, siphon about 15% of the tank’s water into the bucket. When finished, replace
the water with clean tap water that has been treated for chlorine or chloramines. While doing
this, you might place a stiff plastic divider between the area you are cleaning and the fish so
that you do not accidentally suck any up in the tubing.
Additionally, with the siphon running, you can tap the tip down into the gravel to help remove any
fallen debris.
Glass: Take a clean cloth and spray it with window cleaner, away from the tank so that none
gets in the water and then, simply clean off the front and side glass areas.
Water Changes
A key part of aquarium maintenance is the water change, which should be performed about
every two weeks. In most cases, 10-15% of the tank volume is sufficient. A good method is to
replace the water extracted while vacuuming the gravel, which will eliminate uneaten foods
and other residues that settle on the substrate.
It is highly recommended to check the water parameters of both the tank and replacement water.
Most tap water (city water) contains either chlorine or chloramine. Chlorine will air out rather
quickly (kept in an aerated bucked for twenty-four hours); chloramine (chloramine = chlorine
+ ammonia) will not. Using a water conditioner will neutralize the chlorine in both cases, but

19. ammonia will still be present in the latter. It has to be broken down by the nitrifying bacteria
present in the aquarium. This may take longer than your fish can tolerate.
Other elements of municipal water may be phosphates, iron, and other heavy metals. To find
out about your tap water chemistry, call your local water company.
Well water is usually harder than tap water, but is chlorine/chloramine free.
Filtered water should also be checked on a regular basis and should be considered part of your
aquarium maintenance routine. The filter membranes could be damaged or may require
replacement prior to the expiration date.
Testing Aquarium Water
Water chemistry is not visible; therefore, it is vital to check it on a regular basis. The best way
to make this a routine is to check on the tank chemistry while changing the water.
The vital parameters are pH, nitrates, nitrites, and carbonate hardness (salinity for marine
tanks).
Stability is the main factor with pH. pH in the range of 6.5 – 7.5 is suitable for most species,
but they can adjust if slightly out of range.
KH (carbonate hardness) is the indicator of pH stability. It should be kept under close
observation if it comes close to 4.5 dH (degree hardness) or 80 ppm. You must take action if it
decreases any further.
Half a teaspoon of baking soda per twenty-five gallons of water will raise the kH by about 1
dH (17.8 ppm).
Nitrites should be undetectable at all times (except during cycling). If you detect nitrites make
sure you check on ammonia as well.
Nitrates should be kept below 10 ppm in freshwater and 5 ppm in marine and reef (preferably
0 ppm).

20. 3.2 AQUARIUM FILTRATION
The proper function of the filter is essential. Filter inserts (floss, Algone, activated carbon)
should be changed at least every four weeks. A high fish load may require shorter periods.
Trapped particles will decompose in the filter as they would in the tank. The filter should also
be cleaned once a month (do not touch the bio-wheels, if present) by using the water extracted
from the tank during the water change.
3.3 MAINTENANCE PROBLEMS
The design of a large aquarium must take into account the requirements of the specimens,
especially since exhibits at modern aquariums include all types of aquatic organisms:
mammals, birds, reptiles, amphibians, and invertebrates as well as fishes. Among the many
factors that must be considered are traffic flow patterns of visitors, reflections off glass,
acoustics, and tank-maintenance problems such as water clarity, dissolved wastes, temperature,
tank decor, disease treatment, and nutrition.
The primary requirement for maintaining aquatic organisms is water quality. The water supply
must be free of pollutants, including sewage and industrial wastes, and it should be in gaseous
equilibrium with the atmosphere to ensure adequate oxygen and to avoid super-saturation with
nitrogen. In recirculating systems, water treatment must not only ensure clarity of the water but
also purification of metabolic wastes. The source of fresh water is usually water supplies from
which chlorine and other additives have been removed, either by carbon filtration or by the
addition of a chemical. Marine organisms can be maintained in either natural or artificial
seawater; the latter has the advantage of being initially free from disease-causing organisms
and pollutants but may not be as suitable for some organisms.
Water is continuously recirculated in closed systems and is only renewed periodically.
Metabolic wastes must be treated since they are not continuously flushed from the system. An
important problem is that ammonia must be rapidly removed or transformed because it is
harmful even at very low concentrations. In the aquarium the bacteria that convert ammonia to
nitrite reside primarily in the filter material, and a slow sand filter with a large surface area is
usually provided to ensure their abundance. Plant growth in the aquarium, especially in marine
systems, is not usually sufficient to utilize all the nitrate produced by bacteria from nitrite.

21. Although some aquariums have operated many years with a minimum of water renewal, it is
normally necessary to replace from 1 to 10 percent of the water per month to maintain a low
level of nitrates. The use of charcoal in both fresh water and seawater systems helps to slow
the accumulation of nitrogenous wastes. Metabolic wastes also cause an increase in the acidity
of the water. Carbonate compounds are commonly used to maintain an optimal level of acidity,
particularly when water renewal is infrequent.
Semi-closed systems are essentially the same as closed except that there is a constant
connection to the water supply, and the problem of dissolved wastes is controlled by the regular
addition of new water; this system is less costly than the open one with regard to temperature
control and pumping.
Filters vary from simple flow-through systems to completely automated recirculating systems,
with special provisions for monitoring and controlling the physical and chemical characteristics
of the water.
The turnover rate, or rate of water replacement, of individual aquariums is important and should
be no more than two hours. In addition, aeration by means of air stones (diffusers) should be
provided to guard against asphyxia in the event of an unexpected water-supply failure.
Fishes and invertebrates can also be maintained without filtration or aeration in aquariums that
are “balanced” with plants; however, the balance between plants and animals is very difficult
to attain on a large scale or even in a normally stocked aquarium, especially a seawater
aquarium.
Freshwater pools for mammals and birds present special problems. They generally require a
higher filtration rate and greater filter capacity because they accumulate large amounts of faecal
wastes. Air-breathing animals, however, are not highly sensitive to water quality; thus,
chemical treatments, such as chlorination, which would kill fishes, can be used to control
bacteria and to improve water clarity. Seawater formulas are simpler; for example, a 2 per cent
sodium chloride solution will satisfactorily maintain whales and dolphins. Seals and sea lions
have been kept in fresh water, but this may increase their eye problems because of the osmotic
effect of the fresh water on the eye tissues.

22. REFERENCES
Esther JJV. (1998). Encyclopedia of Tropical Fish. Edn 2, Rebo Productions Ltd. The
Netherlands.
Gupta SK, Gupta PC. (2006). General and Applied Ichthyology. Schand Publishers, New
Delhi, 504-519.
Kutz M. (2002). Handbook of material Selection. John Wiley and Sons, 431,.
Pandy K, Shukla JP. (2005). Fish and fisheries. National Offset Printers, Meerut 2005, 461-
473.
Scripps EW. (2006). DIY Networks Aquariums Co. Ltd. Tennessee, USA DIYnet.com