A computer program product, according to one embodiment, includes a computer readable storage medium having program instructions embodied therewith. The computer readable storage medium is not a transitory signal per se. Moreover, the program instructions are readable and/or executable by a controller to cause the controller to perform a method which includes: assigning data having a first heat to a first data stream, assigning data having a second heat to a second data stream, and writing the data streams simultaneously, in parallel, to page-stripes having a same index across a series of planes of memory. The writing of the first data stream begins at an opposite end of the series of planes as the writing of the second data stream, the writing of the streams being toward one another. Other systems, methods, and computer program products are described in additional embodiments.