Spirulina and Algae Farming Farming in India 2026

Spirulina can be grown in India wherever warm, sunny weather and clean alkaline water are available, but it is a factory-style enterprise, not a field crop: it needs lined tanks, a culture of a tested strain, careful water chemistry and a buyer for the dried powder. Reliable Indian figures for yield per square metre and selling price were not available for this page, so ask a source such as CSIR-CFTRI Mysuru, a KVK or a processor for current numbers before you invest.

The technical basics below come from a published review of two large commercial farms in Thailand and the USA. Small Indian units copy the same principles on a smaller scale.

How it is grown

• Culture: spirulina (Arthrospira) grows naturally in alkaline lakes. Farms grow it in shallow open ponds shaped as a rectangular channel (raceway), with a paddle wheel to circulate the water. The Thai farm in the review ran 13 concrete ponds of 2,000 m2 each and the US farm 30 plastic-lined ponds of 5,000 m2 each. A small farm uses a tank of a few square metres.
• Strain: the review stresses that a strain that does well in the laboratory may not behave the same outdoors, so strain selection for local conditions matters. Get the starter culture from a reliable source such as CSIR-CFTRI, which is listed as the developer of a rural spirulina production technology on the government's science and technology portal.
• pH: kept at 9.5 to 10.5 using carbon dioxide. The high alkalinity keeps most competing organisms out, but contamination by other algae, insects and dirt is still the main practical problem.
• Warm weather: the Thai farm, with mean temperatures of 25 to 29 °C, produced all year; the US farm, with a colder winter, could produce only from April to October. Check your winter water temperature before you plan the year.

Culture medium

The review gives a simplified Zarrouk medium, the standard recipe for spirulina. Trace elements are adjusted to your water quality, and nitrate can be replaced by ammonia water if cheaper.

• Use food-grade chemicals and clean water, and keep tanks covered from rain and animals; a food-grade product cannot be made from a contaminated culture.

Harvest, drying and quality

• Harvest: in the commercial farms the algae are filtered through screens and concentrated to a wet cake of about 15% solids.
• Drying: large farms spray-dry the cake to a fine powder and pack it in oxygen-barrier bags to protect the less stable components such as beta-carotene. Small units use low-temperature drying under cover; sun-drying risks contamination and loss of quality.
• Quality yardstick: the Japanese Health Food Association standard quoted in the review asks for crude protein above 50% and moisture below 7%, negative coliform, and limits on arsenic (below 2 ppm) and lead (below 20 ppm). The US FDA limits insect fragments and rodent hair. Indian food-supplement sales fall under FSSAI rules; ask FSSAI or your food-safety officer which licence and tests apply.

Cost and returns

• No verified current Indian figure for tank cost, yield or selling price was available. NABARD has published a model bankable project on spirulina; read its assumptions and update the prices before using them.
• Arithmetic to do yourself: annual income = kg of dry powder harvested per day x harvest days x price per kg you can really get. Get a written price quote from a buyer for your powder grade first, then work back to the tank area you need.
• Costs to list: lined tanks or ponds, paddle or aerator and power, chemicals for the medium, filtering and drying equipment, packing, testing, labour and licences.

Market and risks

• Spirulina sells mostly as a food supplement and health food, as a feed ingredient (especially for aquaculture) and as a blue colour extract, according to the review. Parry Agro Industries is listed in it as an Indian producer. Large producers set the price for bulk powder, so a small farm usually does best selling tablets or capsules or powder directly under its own food licence.
• Be careful with training sellers and "buy-back" schemes that charge a fee for a starter kit and promise monthly income. Ask to see a working farm and its sales records.
• Risks include culture crashes in cold or rainy spells, contamination, lack of a licensed market, and unsold stock.
• For group marketing see FPO; for subsidy options see subsidy finder.

Sources

• Shimamatsu H. (2004), Mass production of Spirulina, an edible microalga, Hydrobiologia 512
• India Science and Technology portal, Rural based biotechnological production of Spirulina (CSIR-CFTRI)