Hi, I am running some microPIV expts in a channel, the dimensions of which are 50mm * 2.5mm* 45um. There ends up being a lot of bubble formation in the channel and I was advised to use some surfactant like Tween 20. I bought a bottle of that. But it doesn't come with any guidelines and to how much should be added. I would appreciate if you could tell me some number as a safe starting point. The flow tracers that I use are carboxylated polystyrene beads in nanopure water. Best Regards, Vishwa