FTSE 100 business outsourcing firm Capita is to buy specialist insurer Fish Administration for £21m on a cash free, debt free basis.Fish provides insurance products to people with disabilities, including cover for adapted vehicles, travel, and mobility scooters, as well as insurance products to the independent living and care sectorsIts operating profit for the 12 months ended May 2011 was £3.5m on a turnover of £5.8m.Capita said the the acquisition from private equity firm Inflexion would add greater capacity and new expertise to its specialist insurance broking business."Fish is the market leader in the field of providing insurance broking services to the independent living anddisability markets," said Paul Pindar, Chief Executive of Capita. "Backed by Capita, and alongside our existing specialist insurance broking business, we anticipate strong potential for growth in the motor, travel, independent living and carer insurance markets, enabling us totake the business from strength to strength."Preston-based Fish will add 30 people to Capita's roster of 45,000 employees.