A fluidic system for a flow-type particle analyzer, comprising: a) a flow cell having a sample fluid inlet port, a sheath fluid inlet port, an outlet port, and a cuvette, wherein said cuvette contains a cuvette channel having a input end and an output end, wherein said input end is in fluidic communication with said sample fluid inlet port and said sheath fluid inlet port, and said output end is in fluidic communication with said outlet port; b) a sample fluid line in fluidic communication with said sample fluid inlet port, for providing a particle-containing sample fluid from a sample fluid container; c) a sheath fluid line (421, 521) in fluidic communication with said sheath fluid inlet port, for providing a sheath fluid from a sheath fluid reservoir; d) an outlet line in fluidic communication with said outlet port; e) a vacuum pump having a controllable power level, in vacuum communication with said outlet line, configured to draw a vacuum in said outlet line, thereby pulling said sample and sheath fluids through said flow cell; wherein the fluid system further comprises: f) a first sensor configured to measure a dynamic pressure drop from the sheath fluid inlet port of the cuvette to said cuvette outlet port; g) a first control feedback circuit configured to regulate the power of said vacuum pump in response to the pressure drop measured by said first sensor; h) a second sensor configured to measure a static pressure drop from said cuvette outlet port to atmospheric pressure; and i) a second control feedback circuit configured to regulate the power of said vacuum pump in response to the pressure drop measured by said second sensor; where said sample fluid line or said sheath fluid line (421, 521) comprises a variable-resistance fluidic resistor (222, 320, 622). a) a flow cell having a sample fluid inlet port, a sheath fluid inlet port, an outlet port, and a cuvette, wherein said cuvette contains a cuvette channel having a input end and an output end, wherein said input end is in fluidic communication with said sample fluid inlet port and said sheath fluid inlet port, and said output end is in fluidic communication with said outlet port; a sample fluid inlet port, a sheath fluid inlet port, an outlet port, and a cuvette, wherein said cuvette contains a cuvette channel having a input end and an output end, wherein said input end is in fluidic communication with said sample fluid inlet port and said sheath fluid inlet port, and said output end is in fluidic communication with said outlet port; b) a sample fluid line in fluidic communication with said sample fluid inlet port, for providing a particle-containing sample fluid from a sample fluid container; c) a sheath fluid line (421, 521) in fluidic communication with said sheath fluid inlet port, for providing a sheath fluid from a sheath fluid reservoir; d) an outlet line in fluidic communication with said outlet port; e) a vacuum pump having a controllable power level, in vacuum communication with said outlet line, configured to draw a vacuum in said outlet line, thereby pulling said sample and sheath fluids through said flow cell; f) a first sensor configured to measure a dynamic pressure drop from the sheath fluid inlet port of the cuvette to said cuvette outlet port; g) a first control feedback circuit configured to regulate the power of said vacuum pump in response to the pressure drop measured by said first sensor; h) a second sensor configured to measure a static pressure drop from said cuvette outlet port to atmospheric pressure; and i) a second control feedback circuit configured to regulate the power of said vacuum pump in response to the pressure drop measured by said second sensor;