So is the knob to the left slower pulsing and to the right faster?
I played with it but couldn't really tell a difference. (I am currently on else mode)
The knob alters the length of the pulse, as well as the timing in between pulses. I believe all the way to the left is shorter pulses, and all the way to the right is longer pulses. The knob only affects modes W1, W2, and W3.
I'll quote myself here with the instructions I found online:
Press the 'MODE' button to cycle through the selection of functions.
"H" Modes do high, constant, non-variable flow:
H1 - 1717 GPH
H2 - 1268 GPH
H3 - 845 GPH
"S" Modes alter the W1 Wavebox function flow strength:
S1 - 100% flow
S2 - 75% flow
S3 - 50% flow
W1: Short pulses which, when timed correctly will create a back and forth motion and form a gentle standing wave in your tank. Adjust the controller to change the speed of the pulses and vary the size of the wave according to your tank.
W2 & W3: Pump gradually speeds up and slows down incrementally to create a varied flow pattern. Adjustable to form the wave best suited to your tank.
Else: Reef Stream Mode. A mixed, changing pattern that creates a random flow cycle similar to what you would find in a natural reef.
Feed: Press the 'FEED' button once and the blue '10min' light will illuminate indicating that the pump has been stopped for 10 minutes. When the time has elapsed, the light will go off and the pump will be turned back on. Alternatively, press the 'FEED' button again to start the pump.
Lock: To prevent changes from inadvertently occurring by accidentally turning the adjustable control knob. Press and hold the 'FEED' button for 5 seconds. The red 'LOCK' light will illuminate and the control knob will no longer function. Press and hold the 'LOCK' light again 5 seconds to disable this feature.
*Night: When the two-pinned sensor is inserted into the two small plugs on the left-hand side of the control box, Night mode will function automatically. The sensor detects when the tank lights go out and slows the pump to half speed. The 'Sensor' light will illuminate when Night mode is in operation. To disable the Night mode function, remove the sensor from the control box.
* Night mode is a new feature intended for use with low output lighting. The sensor can become damaged when used with high output VHO, HQI, and LED lighting systems.