AQUARIUM FISHERIES
►Unit 1 : Introduction to Aquarium Fish Keeping
The potential scope of Aquarium Fish Industry as a Cottage Industry, Exotic and Endemic species of Aquarium Fishes.
Q.What is the potential scope of the aquarium fish keeping industry as a cottage industry?
This art or technique of ornamental fish breeding and trade has a tremendous scope as a cottage industry.
i)It requires very small investment only of a couple of thousand rupees initially.
ii)The money automatically gets generated by the sale of the fish and aquarium accessories.
iii)The further expansion of the business does not require funding through loans etc from the financial institutions.
iv)The whole set-up could be accommodated in the backyard of the cottage.
v)The amount of water required is also not much.
vi)Training of a month or so could equip the entrepreneur to start this business. Later, by practice and experience he or she becomes an expert aquarium fish breeder and even trader.
vii)Ornamental fishes are very easy to breed and even maintain.
viii)Besides, the making of the aquarium fish food from the locally available ingredients, fabrication of different sizes of glass aquaria, small dip-nets, sale of the bottom material in the form of small round stones, coloured gravel, marble chips, plastic toys and even the air diffusers and aerators can be collected and stored or manufactured at the cottage level.
ix)The learner does not require any special formal education.
x)Ornamental fish trade is a multi-million rupees industry in India and virtually multibillion dollar industry in the world. Financial institutions like NABARD, and National Fisheries Board support this industry as a cottage venture.
xi)Kolkata, Mumbai, Chennai, Kochi are the main business centres for this industry who get their supplies from the small entrepreneurs.
Q.What do you mean by classified and non-classified ornamental fish? Give suitable example.
Classified Indian ornamental fish-
The fishes that can be reared in aquarium throughout their life span.
Example-Botia dorio, Danio dangila, Badis badis, Colisa lalia.
Non-classified ornamental fish-
The food fishes that are used in aquaria during their juvenile stage.
Example-Chitala chitala, Labeo gonius, Channa marulius.
Q.Give example of ornamental fish for the following ornamental characters.
(a)Jumping behaviour, (b)Stripes and banding pattern, (c) Beautiful colour.
(a) Esomus danricus, Chela laubuca
(b) Botia rostrata, Botia dario
(c) Tertaodon cutcutia, Colisa lalia
Q.Give example of 3 indigenous freshwater ornamental Fish.
1.Kerala queen ( Puntius denisoni ), 2.Rosy barb ( Puntius conchonius ), Naga danio ( Danio naganensis )
Q.Give example of 3 Exotic freshwater ornamental fish.
1.Platy fish ( Xiphophorus maculatus ), 2.Guppy fish ( Poecilia reticulata ),
3.Molly ( Poecilia latipinna )
Q.Give example of 3 Exotic marine ornamental fish.
1.Fiji Blue Devil Damselfish ( Chrysiptera taupou )
2.Candy basslet ( Lipopoma carmabi )
3.Neptune Grouper ( Cephalopholis igarashiensis )
►Unit 2 : Biology of Aquarium Fishes
Common characters and sexual dimorphism of Fresh water and Marine Aquarium fishes such as Guppy, Molly, Sword tail, Gold fish, Angel fish, Blue morph, Anemone fish and Butterfly fish
Q.What is pearl organ? (or nuptial tubercles)
The organ that appears on the male of many fishes to mark the sexes. e.g. Minnows ( Cyprinidae ) and Suckers ( Castostomidae ).These tubercles are little horny excrescence that become evident just before the spawning season and disappear shortly after, under the influence of hormonal secretion.
iii)The fins often provide characteristic distinctive of the males. For e.g. the lower lobe is greatly extended in the males of the sword tail ( Xiphophorus helleri ). It is somewhat enlarged in white sucker ( Catostomus commersoni ).
Q.Mention sex differences in anabantids and cichlids.
i)The two families have well-marked sex differences in the fully adult fish.
ii)The males tend to have longer and more pointed brilliantly coloured dorsal and anal fins even in the non-breeding season. An anabantid female full of roe is usually very plump, but cichlids show little or nothing.
iii)Sexual selection was observed for female ornamentation in Gobiusculus flavescens, known as two-spotted goby.
iv)Selection of ornamentation within this species suggests that showy female –female competition or male-male choice. Since carotenoid-based ornamentation suggests mate quality, female two spotted guppies that develop colourful orange bellies during the breeding season are considered favourable to males.
v)The males invest heavily in offspring during the incubation, which leads to the sexual preference on colourful females due to higher egg quality.
►Unit 3 : Food and feeding of Aquarium fishes
Use of live fish feed organisms. Preparation and composition of formulated fish feeds
Q.What is batch culture?
This is the simplest and most widely practiced technique. The technique consists of a single inoculation of cells into a container of nutrient enriched-water. Nutrient (NPK-in the ratio of 5:15:3) are added to the water. The commercial fertilizers used in the purpose are Urea (107ppm), single superphosphate (1071ppm) and muriate of potash (77ppm) per litre of water. The pH of the medium is maintained at-8.5. It is grown for 7 to 5 days and harvested.
Q.What is the importance of Artemia culture? Q.How to initiate Artemia culture?
i)Artemia are commonly known as sea monkey or brine shrimp.
ii)They inhibit salt pan waters of more than 200% salt content.
iii)Their cyst can be stored for many years. For laboratory hatching, the dried cysts are allowed to float on surface of filtered normal sea water.
iv)The cysts hatch in 24-48 hours depending on the ambient temperature.
v)Prior to hatching hypochlorite or potassium hypochlorite which helps in the removal of the chorion in 5-10 seconds.
vi)Eggs can also be incubated in a solution made up of 2 teaspoons of common salt mixed in 1 Litre of freshwater.
vii)For mass culture of Artemia, about 250 gm of cysts are a sprinkled in 100 litre of 30-35% sea water.
ix)Temperature must be maintained at 26-30°C.
Q.What are the basic nutritional requirements of fish?
The feed for aquarium fishes should be nutritionally adequate. It must also be palatable. The feed should be made up of the following components:
Protein:
i)It is required by fish for proper growth and maintenance.
ii)All aquarium fishes require arginine, lysine, histidine, thiamine, methionine, valine, leucine, isoleucine, phenylalaline and tryptophan.
Proper amount of non essential amino acids is also included.
For this meat and bone meal, beef and cotton seed soybean meals and microbial source of protein are also used.
The feed should contain 30-40% protein. The protein must be in digestible form.
Lipid:
i)Lipids are needed for energy (calorie). They are also needed for normal biomembrane and organelles.
ii)Fishes have been successfully grown on diet containing 10 % fat.
iii)Cold water aquarium fishes have been grown on high making point animal fats.
iv)Energy deficiency may lead to stunted growth.
v)Excess fats are deposited in the liver, kidney and heart.
Some fatty acids must be supplied in proper amount with the diet, as they can not be synthesized by the fish.
Fatty acid deficiencies have been linked to fin rot and heart disease leading to death.
Carbohydrates:
It has been proved that precooked starch is much more readily utilized by fishes. Some aquarium fishes have been observed to take chitin.
Chitin is digested by some bacteria present in gastrointestinal cavity of fish.
Vitamins:
Fishes require absolute amount of water soluble fat soluble vitamins. Add vitamix (1%) in fish diet.
A considerable amount of minerals are required in the diet.
The main minerals are Ca, P, Mg. These help in increasing growth rate of aquarium fishes.
Q.Give example of two Spirulina culture centres in India.
1.Murugappa Chettiar Research Centre, Chennai.
2.Central Food Technology and Research Centre (CFTRI), Mysore.
Q.State possible disadvantages of using raw fish as a main ingredient.
i)They are harmful to the health and growth of fish primarily due to the presence of the anti-nutrient thiamine. Thiaminase, an enzyme destroy thiamine one of the essential water soluble vitamins (B1) is mostly found in freshwater fish and is destroyed by heat (cooking).
ii)Spead of infectious diseases such as mycobacteriosis and bottulism. In preparing diets, preferential use of marine fish is suggested to minimize thiaminase activity and raw fish could be steamed or poached.
Aquarium fish as larval predator
►Unit 4 : Fish Transportation
Live fish transport - Fish handling, packing and forwarding techniques.
Q.Mention reasons for transporting ornamental fish by using modern packaging technology.
In the ornamental fish trade, the customers’ need for high-quality fish is always a crucial factor. The fish must not only attractive but also robust to withstand long air transportation. The use of modern packaging technology for air transport to increase fish density and improve survival is critical to the industry. There are 4 main reasons for transporting aquatic animals:
(i)The movement of fry or juveniles for stocking into farms or in to the natural environment.
(ii)The movement of brood stock for management purposes.
(iii)The movement of livestock to markets.
(iv)The movement of animals for research purposes.
Q. Give short notes on methods of transportation of aquarium fish.
The transportations of live aquarium fish involve the following steps:
a)Conditioning, b)Containers, c)Control and d)Sedation.
a)Conditioning:
i)Before packing and transport, the ornamental fishes are subjected to conditioning, by keeping them in clear running water in separate tanks for starvation.
ii)Feeding is stopped 24 hours before transport.
iii)Conditioning helps lower stress, metabolic rate and Oxygen consumption in the fish. Starving of the fish helps reduce fouling of the holding water by fish faeces during transport.
iv)It also helps reduce mortality during transport and aids in increasing packing density. The conditioned fish can be shipped over a longer distance.
v)After conditioning, the fishes are placed in the transportation containers.
b)Containers:
i)A wide range of transportation containers are available.
ii)Many varieties of open, small scale, simple containers are used in rural areas where small numbers of animals are to be carried or even large number of young larvae. The containers can be made of plastic, wood or metal.
iii)Earthenware pots can provide significant evaporative cooling.
iv)The sealed containers made of plastic, metal or glasses have also been used but the most widely used closed container is the use of plastic bag. In this the fishes are placed in a volume of water filling about 20% of the bag and the remainder of the bag is filled with pure oxygen which is bubbled through the water during the filling process. The bag is then tightly sealed for the journey but more oxygen could be added if required during transport. To avoid damage by the fish, the plastic bag is covered with paper and then put into one or two other plastic bags of the same size.
►Unit 5: Maintenance of Aquarium
General Aquarium maintenance – budget for setting up an Aquarium Fish Farm as a Cottage Industry
Q.Make a list of suggestions for proper maintenance of an aquarium.
i)Fish scales inspection, examine for any decolouration, growths or wounds, scales that are missing is a fighting indication.
ii)Observation of the fish respiratory rates, slower or faster rate than normal is a sign of problem.
iii)Fish eyes clarity checking, blood or cloudiness should not be present.
iv)Observation of the fish abnormal behaviour such as unusual swimming pattern or sluggishness
v)Regular checking of the tank to ensure that dying or dead fish is not present
vi)Observation of all the fish individually for behavioural patterns familiarization so that it is easier to determine a sick fish in the future
vii)Feed your fish with one-day intervals using diet variations.
viii)Replace the evaporated water on the tank with dechlorinated water.
ix)Once a week, removed 5 to 10 percent of the tank water replacing it fresh dechlorinated water. Unwanted chemicals in the tank are diluted helping the tanks internal environment similar to tap water.
x)Algae scraping from the walls of the tank done once a week
xi)Filter pads checking every two weeks cleaning or replacing them if necessary.
xii)Water testing done every two weeks. Water change is done after one day.
xiii)Ammonia, nitrate, pH levels or nitrite checking done every two weeks
xiv)Drain off the debris from the gravel done once a month
xv)Always keep track the chemical contents of your aquarium and schedule maintenance.
Q.State reasons for using plants and gravel in decoration of aquarium.
Plants: They are the most beautiful, inexpensive source of decoration for your aquariums. Fishes love the aquatic plants as they are part of their natural habitats. Plants are very useful as well, they bind carbon dioxide and oxygenate the water. They also use organic waste products as nutrition and remove potentially harmful compounds from the water. Plants can also be used to keep a check on the water quality of an aquarium, the plant will start dyeing before the fish if the water suddenly becomes toxic.
Gravel or Sand: Both are presents great variety of colours. Gravel comes in white, brown, black and white, red, green and yellow the whole rainbow spectrum. Sand again also has a plethora of colours white, black, red, green and yellow. Both of these can be layered in multiple colours.