Introduction

The global population is expected to reach 9.6 billion by Yr. 2050 and as the demand

for animal protein is increasing year by year it

is a challenge to provide quality protein by

safeguarding its natural resources for future

generations. In this context, aquaculture plays

a key role in promoting health by providing

animal protein as well as generating

employment and economic growth.

Biofloc Technology (BFT) is considered as new

“blue revolution” since nutrients can be continuously recycled and reused in the

culture medium, benefited by the minimum or zero-water exchange. BFT is an

environment friendly aquaculture technique based on in-situ microorganism

production. Biofloc is the suspended growth in ponds/tanks which is the aggregates

of living and dead particulate organic matter, phytoplankton, bacteria and grazers of

the bacteria. It is the utilization of microbial processes within the pond/tank itself to

provide food resources for cultured organism while at the same time acts as a water

treatment remedy. Thus, this system is also called as active suspension ponds or

heterotrophic ponds or even green soup ponds.

How BFT works?

Biofloc system is a wastewater treatment which has gained vital importance as

an approach in aquaculture.

The principle of the technique is to maintain the higher C-N ratio by adding

carbohydrate source and the water quality is improved through the production

of high quality single cell microbial protein

In such condition, heterotrophic microbial growth occurs which assimilates the

nitrogenous waste that can be exploited by the cultured species as a feed and

also works as bioreactor controlling of water quality.

Immobilization of toxic nitrogen species occurs more rapidly in biofloc because

of the growth rate and microbial production per unit substrate of heterotrophs

are ten-times greater than that of the autotrophic nitrifying bacteria.

This technology is based on the principle of flocculation within the system

3

Composition and Nutritional Value of Biofloc

Biofloc is a heterogeneous aggregate of suspended particles and variety of

microorganisms associated with extracellular polymeric substances. It is composed of

microorganisms such as bacteria, algae, fungi, invertebrates and detritus, etc.

It is a protein rich live feed formed as a result

of conversion of unused feed and excreta into a

natural food in a culture system on exposure to

sunlight and vigorous aeration.

Each floc is held together in a loose matrix of

mucus that is secreted by bacteria and bound

by filamentous microorganisms or electrostatic

attraction. Large flocs can be seen with the

naked eye, but most of them are microscopic.

Floc size range from 50 – 200 micron.

A good nutritional value is found in Biofloc. The dry weight protein ranges from 25 –

50%, fat ranges 0.5 – 15%. It is a good source of vitamins and minerals, particularly

phosphorous. It has an effect similar to probiotics. The dried biofloc is proposed as an

ingredient to replace the fishmeal or soybean in the feed.

Advantage of BFT

Eco-friendly culture system.

It reduces environmental impact.

Judicial use of land and water

Limited or zero water exchange system

Higher productivity (It enhances survival rate, growth performance, better

feed conversion in the culture systems of fish).

Higher biosecurity.

Reduces water pollution and mitigate the risk of introduction and spread of

pathogens

It reduces utilization of protein rich feed and cost of standard feed.

It reduces the pressure on capture fisheries i.e., use of cheaper food fish and

trash fish for fish feed formulation.

4

Species suitable for Biofloc Culture

Major cultivable fish species in BFT

A basic factor in designing a biofloc system is the species to be cultured. Biofloc system

works best with species that are able to derive some nutritional benefits from the direct

consumption of floc. Biofloc system is most suitable for species that can tolerate high

solids concentration in water and are generally tolerant of poor water quality. Some

of the species that are suitable for BFT are:

Air breathing fish like Singhi (Heteropneustes fossilis), Magur (Clarias batrachus),

Pabda (Ompok pabda), Anabas/Koi (Anabas testudineus), Pangasius

(Pangasianodan hypophthalmus)

Non air-breathing fishes like Common Carp (Cyprinus carpio), Rohu (Labeo

rohita), Tilapia (Oreochromis niloticus), Milkfish (Chanos chanos)

Shellfishes like Vannamei (Litopenaeus vannamei) and Tiger Shrimp (Penaeus

monodon)

How to Prepare the Inoculum?

Method 1:

For 15000 Litres of fresh water 150 Litres of inoculum is required for the floc development

Step 1

Take clean tub/can with 150 Litres of water and continue vigorous aeration

Step 2

Add 3 Kg of pond soil

+

1.5 gm of Ammonium sulphate /Urea

+

30 gm of carbon source (Jagerry /Wheat flour /Tapioca flour)

Step 3

Mix it well with water in tub and provide adequate aeration

Step 4

The inoculum will be ready after 24-48 hrs and it can be transferred to main tank

5

Daily addition of carbon source is required for the development of floc. For

every 1 kg of feed given (with 25 % of crude protein), 600 gm of carbon source

is to be added to the system to maintain C: N of 10:1.

Once the floc volume reaches 15-20ml further addition of carbon source is not

required

Method II:

Step 1

Take clean tub/can with 130 Litres of water and continue vigorous aeration

Step 2

Add 20 Litres of pond water/RAS water (before filtration)

+

30 gm of carbon source (Jagerry /Wheat flour /Tapioca flour)

+

10 gm of probiotic (with Bacilus Sp., Aspergilus Sp. etc with a total concentration of

10x109 CFU/gm)

Follow the remaining steps as mentioned in method 1

*NB: Well developed inoculum will be turbid with foam on the water surface

(Ideal Volume of Floc in Imhoff cone for shrimp is 10-15 ml/L and

for Fish 25-35 ml/L)

Floc volume measurement with Imhoff con

6

Technical Specifications- 100 m3 (7 Tanks)

S.No Component Details

1 Area for 7 tanks 200 m2

2 Biofloc Tank size 4 metre diameter and 1.5 meter height (1.20 m water

depth)

3 Water holding capacity of

each tank

15,000 Litres capacity

4 Water quality parameters Dissolved Oxygen-5mg/L, Temparature-26-34°C,

pH-7.5 to 8, TDS-600ppm, Floc density-25-40 mg/l,

Ammonia-0.5 ppm, Nitrite-0.3 ppm, Nitrate-150

ppm, Alkalinity-120-280 ppm

5 Tanks Made-up of Tarpaulin/Fibre/HDPE

6 Stocking density 100 nos/m3 (1000 no.s per 15,000 litres tank -

depending on species )

7 Species cultured GIFT Tilapia (Oreochromis niloticus)

8 Survival (%) 80

9 Type of feed to be used floating pellet feed

10 % of feed 2-3% per Average Body weight

11 Feeding frequency 4 times early stage, later 2 times per day

12 FCR 1:1.2

13 Duration of culture 6 months

14 Size/weight of the

species(gm)

500 gm average weight

15 No. of crops per year 2

16 Production 4.2 Tonnes per crop (600kg per tank per crop)

17 Farm gate price(Rs) 130/- kg fish

18 Capital cost 6.00 Lakhs

19 Input cost 1.5 lakhs per one crop

20 Total project cost 7.5 lakh

[11:05 PM, 5/1/2021] priyanshu68: 7

Cost Estimates of Biofloc Unit with 7 Tanks

S.No Component Nos Cost

(Rs)

Total

(Rs in lakhs)

Capital cost

1 Setup of Tarpaulin/Fibre

tanks(15,000 Litres capacity)

7 25,000 1.75

2 Shed material and accessories

fixing charges

200

m2

120000 1.20

3 Water supply borewell(3HP) 1 100000 1.00

4 PVC pipe fittings for air, water

flow

LS 75000 0.75

5 Nets and accessories 5 3000 0.15

6 One Blower (1 HP), Air stones and

other accessories

1 30000 0.30

7 Electrification LS 10000 0.10

8 Power generator(2 KVA) 1 45000 0.45

9 Weighing balance 1 5000 0.10

10 Miscellaneous expenses 0.20

Total Capital Cost 6.00

*Input cost for one crop

11 Seed cost, Feed cost, Probiotics, Test kits etc. 1.50

Total Input cost (per one crop) 1.50

Grand Total 7.50

*input cost may vary depending on stocking density

Economic feasibility (one crop) from 7 Tanks

Sl Components Amount (Rs in lakhs)

1 Capital Cost 6.00

2 Operational Cost 1.50

3 Total project Cost 7.50

4 Gross income per crop 5.46

5

Gross income at the end of one crop after deducting the

recurring cost for the 2nd crop

3.96

6 Gross income from the 2nd crop 5.46

7 Gross income at the end of 2nd crop 9.42

8 Depreciation/maintenance @ 15% of capital cost 0.975

9 Interest @ 12% of TPC 0.90

10 Repayment @ 1/7th of the TPC 1.07

11 Recurring cost for the next crop 1.50

12

Net profit at the end of 2nd crop

9.42- (0.975+0.9+1.07+1.50) 4.975

[11:05 PM, 5/1/2021] priyanshu68: 8

Model Cost Calculation

Model Capital Cost Break up for Biofloc with 50 tanks of 4m dia and 1.5 m

height

S.No Component Nos Cost

(Rs)

Total

(Rs in lakhs)

Capital cost

1 Setup of Tarpaulin/Fibre tanks(15,000

Litres capacity)

50 25,000 12.50

2 Shed material and accessories fixing

charges

1600 m2

600/m2

9.60

3 Water supply bore well and pump (2

nos. of 3 HP)

- 150000 1.50

4 PVC pipe fittings for air, water flow LS 550000 5.50

5 Nets and accessories 50 3000/tank 1. 50

6 Blower (1 HP), Air stones and other

accessories

8 30000 2.40

7 Electrification LS 200000 2.00

8 Power generator(5 KVA) 1 150000 1.50

9 Miscellaneous expenses 0.50

Sub Total 35.50

*Input cost for one crop

(*input cost may vary depending on stocking density)

10 Seed @Rs.4/- for 50000 2.00

11 Feed cost @Rs.30/kg for 24 T 7.20

12 Probiotics, carbon source, test kits, electricity etc. 5.30

Sub total 14.50

Grand Total 50.00

9

Model Capital Cost Break up for Biofloc with 25 tanks of 4m dia and 1.5 height

S.No Component Nos Cost

(Rs)

Total

(Rs in lakhs)

Capital cost

1 Setup of Tarpaulin/Fibre

tanks(15,000 Litres capacity)

25 25,000 6.25

2 Shed material and accessories

fixing charges

800 m2

600/ m2

4.80

3 Water supply bore well and

pump (2 nos. of 3 HP)

1 150000 1.50

4 PVC pipe fittings for air, water

flow

LS 250000 2.50

5 Nets and accessories 25 3000/tank 0.75

6 Blower (1HP), Air stones and

other accessories

4 30000 1.20

7 Electrification LS 100000 1.00

8 Power generator(5 KVA) 1 150000 1.50

9 Miscellaneous expenses 0.50

Sub Total 20.00

*Input cost for one crop

(*input cost may vary depending on stocking density)

11 Seed cost @ Rs.4 for 25000 1.00

12 Feed cost @ Rs.30/kg for 12 T 3.60

13 Test kit, carbon source, electricity charges etc. 0.40

Sub Total 5.00

Grand Total 25.00

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Model Cost Break up for Construction of Biofloc ponds for Brackish water/

Saline/ Alkaline areas including inputs of Rs. 8 lakhs/0.1Ha

Input Costs

Sl. No Components Total Amount (in

Lakhs)

1 Seed cost @ Rs.0.40/pc for 300000 1.20

2 Feed cost @ Rs.70/kg for 6MT 4.20

3 Electricity and fuel 1.00

4 Harvesting charges 0.20

5 Miscellaneous/transportation etc 0.60

Total 8.00

Grand Total: Rs. 18 lakhs

Capital cost

S.No Component Total

(Rs in lakhs)

1 Earth work excavation and construction of bund 0.50

2 Polyethylene lining 1.50

3 Inlet, outlet and central drainage system 0.50

4 PVC pipe fittings for air, water flow 0.50

5 Pump house-100sqf 1.00

6 Pumps-1 nos. 3 HP 0.30

7 Aerator-4 nos. @Rs.25,000 0.70

8 Air Blower 0.30

9 Aeration tubes 0.30

10 Generator set 10 KVA 2.00

11 Net, Imhoff cone, weighing balance, water testing kits and other

accessories

0.30

12 Bio security Measure-Bird net, crab net 0.20

13 Electrification L.S. 0.50

14 Watchman shed-10sqf 1.00

13 Miscellaneous 0.40

Total 10.00

12

Biofloc Scheme under PMMSY-

Beneficiary oriented sub-components and activities

S.no. Sub-component and activities Unit Unit

cost

(Rs.

Lakhs)

Page No.

A Enhancement of production and productivity

1 Development of inland fisheries and aquaculture

1.11 Construction of biofloc ponds for

brackish water/saline/alkaline areas

including inputs of rs.8 lakhs/ha

0.1

ha

18.00 85-86

1.12 Construction of biofloc ponds for

freshwater areas including inputs of rs.4

lakhs/ha

0.1

ha

14.00 86-87

5 Technology infusion and adaptation

5.1 Biofloc (50 tanks of 4m dia and 1.5

high) culture system.

(No) 50.00 120

5.2 Biofloc culture system (25 tanks of 4m

dia and 1.m

(No) 25.00 120

5.3 Biofloc (7 tanks of 4m dia and 1.5 high)

culture system

(No) 7.50 121

How to avail subsidy?

Beneficiary needs to submit the project report (PR) along with required

documents including documentary evidence of availability of requisite land

(either own/registered lease document to the concerned District Fisheries

Office for further process. In case of leased land, proper registered lease

document for a period of 7(seven) years from the date of submission of SCP

will have to be submitted.

Project report (PR) with full justification & technical-economical details

including the species to be cultured, capital cost and the recurring cost

involved. Project report should also contain details of anticipated direct &

indirect employment generation to local population, enhancement of fish

production, specific time lines for implementation of project etc has to be

furnished to DFO

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In case of Biofloc in Pond, the governmental assistance is restricted to (a) 2 units

of 0.1 ha per individual beneficiary, (b) 2 units of 0.1 ha multiplied by the

number of members of the group/society with a ceiling of 20 units of 0.1 ha per

group/society in case of Groups of fishers and fish farmers i.e. fisher

SHGs/Joint Liability Groups (JLGs)/Fisher Cooperatives etc. or those

undertaken in a cluster/area approach.

In case of Biofloc in tank, governmental assistance will be restricted to one unit

of large or one unit of Medium or 1 of small BFT for individual beneficiary.

Governmental assistance will be restricted to 2 units of large or 3 unit of

Medium or 4 units of Small BFT per group/society in case they are taken up by

Groups of fishers and fish farmers

However, a cluster/area may have multiple groups/societies. As far as

FFPOs/Cs are concerned, the modalities of implementation and upper ceiling

on the total area eligible for support would be decided by the CAC.