Today i have ordered some new test boards with a total of 9 pcb coils. These have different turns, and three of these coils also have a 5mm diameter hole in the middle to test them with an iron core. This should increase the magnetic field of the windings and attract stronger the ferrofluid.
The magnetic field of the windings need to be a little stronger but the concept seems to be working.
The idea is to have ferrofluid dancing around from a simple PCB. This is obviously just a concept but with more windings and perhaps with a core in the middle of these printed windings, it can be possible. (Also, I need to find a way not to stain the container with the ferrofluid .. its a little messy)
This was tested with my open source Linear PCB Motor board: