within stack beams 20 constrained by two guide channels 10 in opposition in step 204 method 200 lowers picker mechanism 30 until picker beam 31 reaches a stack beam 20 corresponding to the desired gate opening height in step 206 method 200 inserts a portion of picker beam 31 between stack beam flanges 22 a and 22 b of at least one of the plurality of stack beams 20 in one embodiment method 200 inserts at least one of picker beam flanges 33 a and 33 b between stack beam flanges 22 a and 22 b in step 208 method 200 applies a lifting force to picker beam 31 through picker rod 37 in one embodiment application of the lifting force includes actuating a mechanical device providing the lifting force in step 210 method 200 raises at least one of the plurality of stack beams 20 along guide channels 10 fig3 is a flowchart illustrating an exemplary embodiment of a method 300 for installing an incrementally adjustable fluid control system 100 in step 302 method 300 fixes two guide channels 10 in opposition in certain embodiments guide channels 10 bracket a fluid channel in other embodiments multiple guide channels 10 may be attached along their respective guide channel webs 12 to connect multiple incrementally adjustable fluid control systems 100 in still other embodiments guide channels 10 may be attached along their respective guide channel webs 12 to posts or other structures within a fluid.