Methods and apparatus are provided for controlling data management operations including storage of data in solid state storage (6) of a solid state storage system (5). Input data is stored in successive groups of data write locations in the solid state storage (6). Each group comprises a set of write locations in each of a plurality of logical subdivisions of the solid state storage (6). The input data to be stored in each group is encoded in accordance with first and second linear error correction codes. The encoding is performed by constructing from the input data to be stored in each group a logical array of rows and columns of data symbols. The rows and columns are respectively encoded in accordance with the first and second linear error correction codes to produce an encoded array in which all rows correspond to respective first codewords and columns correspond to respective second codewords. The encoding and storage operation is performed such that, in each said group, the encoded input data comprises a plurality of first codewords in each of a plurality of the logical subdivisions and each logical subdivision contains a portion of each of the second codewords for that group.