Unique Culture System

Introduction: Nature Park is mainly known as Mudialy Fishermen’s Cooperative Society (MFCS). Nature Park or MFCS mainly deals with wastewater processing and pisciculture. 

Brief Idea on MFCS: MFCS is situated in the south – western fringe of Kolkata. It is mainly water logged wasteland filled with water hyacinth used by Kolkata Port Trust for dumping garbages. 

Aim of MFCS : The main activity of this co-operative is to produce quality fish by using processed waste water. 

Necessity of Waste Water Processing: Wastewater including domestic sewage and waste from mainly agro-industrial areas can be purified step by step. Purified sewage or agro- industrial water can be reused after proper treatment for pisciculture as nutrient and mineral contents of water are recycled. With the help of waste water treatment method not only we can solve our water shortage problem but also we can use this water for pisciculture. 

Source of Waste (INLETS) : Wastes from more than 47 industries are coming to the MFCS and get processed. In the list of industries various petrol pump and petroleum companies namely Hindustan petroleum, factories like steel, leather, metal box etc, well known manufacturing companies like Voltus, Hindustan Sanitaryware, Balmer Lawrie, I.T.C, Brooke Bond, Kajaria etc, are included and many more. Domestic sewages  are coming from KOPT.(Kolkata Port Trust) quarters.

Outlets: Ganga through Moni Khal (canal). 

Basic Culture Protocol: The basic principle of waste water processing in the MFCS is totally carried out in a natural way. 

Whether the Water Is Flowing Or Stagnant In Nature: Water is flowing in nature. 

Flora and fauna in MFCS : 

Flora: Various kind of algae (mainly chlorophyta- green algae), azolla (Azolla pinnata), water hyacinth (Eichhornia crassipes). 

Fauna: The dominant types of fish fauna identifies in their ponds are 14,prawn and crat fauna are  three, snail fauna is three and snake fauna is three. Besides this more than one species of fish – namely, ‘Chanda’, ’Mourala’ and ‘Punti’ which are known to be fresh water varieties of sensitive nature. 

Waste Water Treatment Procedure In MFCS :  

• Waste water come into the inlet pond.

• At first waste water passes through six ponds known as ‘ANAEROBIC TANKS’.

• Within anaerobic tanks water is treated with lime  whichserves to neutralise acids while precipitating various metals into solids that can be recovered. 

• Water hyacinths are kept in the tanks. Hyacinth is a well known saprophytic plants that derive nutrition from dead and decaying matter, so these plants are used to facilitate the absorption of oil , grease and toxic materials.

• The second tank into which water moves from first through a narrow passage(culvert at the upper level).

• This place is used to rear exotic, predatory, omnivorous fishes like singhi(Heteropneustes ), magur (Clariassp.),koi ( Anabas sp.) which are used as natural pollution indicators. 

• After that water flows into third pond through a canal which is filled up with saprophytic water hyacinth.

• By this way the water quality is improving in each step and mineral contents of the waste water can be recycled and now water can be utilised for pisciculture.

Canal Lock Gate: Lock gate system is also used in this system, one lock gate at entry of waste water and another is at discharge or exit site(or the point where water moves to another pond). 

Positive aspects of waste water processing: 

• Through the waste water treatment level of suspended, dissolved, volatile solids, alkalinity, phosphate, COD,BOD can be lowered . This purified wastewater can be used for cultivation of fishes.

• By treating wastewater it serves proper scope for purification which in turn decreasing the water pollution as well as provides protection of environment from pollution.

• This treatment helps to produce disease free fishes.

• Wastewater treatment ensures large amount of aquatic resources.

Treatment & pisciculture in MFCS:  

• Regular fishing in wetland areas plays a vital role in purifying the pollution of environment as well as maintaining ecological balance.

• Fishes like catla (Catlacatla), Rohu (Labio rohita),bata ( Labeo bata ),mrigal (Cirrhinus mrigala),common carp (Cyprinus carpio), silver carp (Hypophthalmichthyes molitrix) etc. 

• It has been observed that there is less possibility of disease occurence in fishes because this water is totally purified.

Uniqueness of MFCS otherthan east kolkata wetland: 

In MFCS waste water is processed by canal system, so sedimentation takes place which helps to process the water in better way.In case of East Kolkata Wetland settling tank, oxidising tanks and solar energy  are used to degrade organic compounds. 

The 1990 NEERI report testifies that the climatic condition of the area  facilitates conversion of organic waste into protein rich micro algae for raising a fine catch of fish without much supplementary feeding,reducing the cost of aquaculture. 

Regular monitoring is done in MFCS. Monitoring by regular fishing is important as if any diseased fishes are found during fishing then it will be an indicator for quality of  water. 

MFCS  is maintaining wetland which is known as  nature’s kidney.By processing the waste water and culturing the fishes within this processed water MFCS is maintaining biodiversity balance. 

Limitation of the wastewater treatment:  

• By using natural water hyacinth the process becomes slow . It consumes long time to purify sewage and industrial water.

• Some scientific gadgets can be used for the waste water-treatment. Filters & chimneys can be introduced to the initial step so that the process can be conducted faster.

• Although this process is scientifically approved still it is not introduced to local drainage system , regular domestic sewage system and Ganga water processing.

• Till now this treatment procedure is not included for  chemically  treated water . 

MFCS is Not Under the Limelight: 

MFCS has won the national productivity award for a record five times for its fish production. Despite the hard work of members as well as fishermen,still  they have not received much appreciation and recognition.Their unique efforts and the culture system is not known to the worldwide. 

Future investigation: 

There is no complaints against the cultured fishes in this water. Fish growth is quite normal.Fish health is also normal. Consumers like the taste of cultured fish, which means from organoleptic point of view that this waste water processing & pisciculture is acceptable but we have to prove beyond any doubts that fish produced in such a system is totally safe for human consumption. 

Future strategy of my work is to prove beyond any doubts & to make this processed waste water pisciculture scientifically acceptable.