Question 1: My tank is 89"x24" (23" top to bottom). Do I need 3x or 4x LX7206 light fixtures?

Question 2: I have 2x VarioS 8 pumps that support a 0-10V interface. What connector do I need to hook them up? I obviously need a YL2-1 splitter cable, but I don't know what else I need.

Question 3: Can I put a PLM-PWC, PLM-pH/Redox-2Level, and a PLM-pH/Redox in a Profilux 4 all at once?

Question 4: What does is the advantage of the Measurement Cell vs the Sensorholder 4?

Question 5: What kind of flow rate should go through the Measurement Cell?