I am using a syringe pump to feed 9 wells microfluidics chip, for one case I need a separate flow for each row of the chip ( 3 inlets ) and for a second case I need a separate flow of each well ( 9 inlets ) ..

Since it's not convenient to use 3 syringe pumps for the first case or 9 for the 2nd one I decided to use a splitter ( see the picture below ) ..

With the splitter the flow is going okay in some of the inlets but not all of them and I am failing to figure out why ,

Is there any other more effective way to be used ? Also are there any special things I need to check when using such splitter

Ps: the syringe pump flow for the first case is 6 microL/min and for the 2nd case is 18 microL/min

Thanks!