What I probably meant is Brushless (for quietness), and with the ability to dispense a set, measured amount [vs. the knob control 1-10], plus the ability to remote control through voltage [so I can also use the Apex varspeed control], even more specific - a 600 RPM model with a head that accepts the larger of the L/S tubing [size 18 or 35; 18 has a smaller wall thickness, hence the 35 can sustain a stronger pressure / higher head].
What is my actual goal? - to be able to do a controlled continuous water change, PLUS, having the ability to do an occasional big water change using the pump (by ramping up the RPM).
So, I narrowed it down to these models: 7523-60, 7555-30; modular: 77301-20, 77301-30; washdown 7575-00.
Of course, I'd always welcome any advice/idea.
