A method of processing a sample, comprising: placing a sample comprising a liquid into a processing chamber of an apparatus, the apparatus comprising: a body comprising a first end and a second end opposite the first end, the body comprising: a processing chamber comprising an opening (124, 134, 144) proximate the first end; a first reservoir disposed in selective fluid communication with the processing chamber via a first fluid pathway; a second reservoir disposed in selective fluid communication with the processing chamber via a second fluid pathway; a filter disposed in the body between at least a portion of the processing chamber and the second reservoir; wherein the first fluid pathway and the second fluid pathway pass through the filter; wherein the filter has a first surface oriented in the fluid pathways (195, 197) toward the processing chamber; a first one-way valve disposed in the first fluid pathway between the filter and the first reservoir, the first one-way valve providing selective fluid communication between the processing chamber and the first reservoir; and a second one-way valve disposed in the second fluid pathway between the filter and the second reservoir, the second one-way valve providing selective fluid communication between the processing chamber and the second reservoir; urging at least a portion of the liquid out of the processing chamber through the filter; after urging the at least a portion of the liquid through the filter, urging a first portion of a back-flush liquid from the first reservoir through the filter and into the process chamber to form a first processed sample; and analyzing at least a portion of the sample to detect an indication of a microorganism, wherein analyzing at least a portion of the sample comprises analyzing at least a portion of the first processed sample. placing a sample comprising a liquid into a processing chamber of an apparatus, the apparatus comprising: a body comprising a first end and a second end opposite the first end, the body comprising: a processing chamber comprising an opening (124, 134, 144) proximate the first end; a first reservoir disposed in selective fluid communication with the processing chamber via a first fluid pathway; a second reservoir disposed in selective fluid communication with the processing chamber via a second fluid pathway; a filter disposed in the body between at least a portion of the processing chamber and the second reservoir; wherein the first fluid pathway and the second fluid pathway pass through the filter; wherein the filter has a first surface oriented in the fluid pathways (195, 197) toward the processing chamber; a first one-way valve disposed in the first fluid pathway between the filter and the first reservoir, the first one-way valve providing selective fluid communication between the processing chamber and the first reservoir; and a second one-way valve disposed in the second fluid pathway between the filter and the second reservoir, the second one-way valve providing selective fluid communication between the processing chamber and the second reservoir; a body comprising a first end and a second end opposite the first end, the body comprising: a processing chamber comprising an opening (124, 134, 144) proximate the first end; a first reservoir disposed in selective fluid communication with the processing chamber via a first fluid pathway; a second reservoir disposed in selective fluid communication with the processing chamber via a second fluid pathway; a filter disposed in the body between at least a portion of the processing chamber and the second reservoir; wherein the first fluid pathway and the second fluid pathway pass through the filter; wherein the filter has a first surface oriented in the fluid pathways (195, 197) toward the processing chamber; a first one-way valve disposed in the first fluid pathway between the filter and the first reservoir, the first one-way valve providing selective fluid communication between the processing chamber and the first reservoir; and a second one-way valve disposed in the second fluid pathway between the filter and the second reservoir, the second one-way valve providing selective fluid communication between the processing chamber and the second reservoir; urging at least a portion of the liquid out of the processing chamber through the filter; after urging the at least a portion of the liquid through the filter, urging a first portion of a back-flush liquid from the first reservoir through the filter and into the process chamber to form a first processed sample; and analyzing at least a portion of the sample to detect an indication of a microorganism, wherein analyzing at least a portion of the sample comprises analyzing at least a portion of the first processed sample.