Growing algae in huge plastic bags

I am predicting a moderate breakthrough in  our ability to grow algae fuels. Bags that can pass small ions, leave out the big molecules.  Use local pumps to strain the good stuff from the ocean water, pump it through the clear plastic bags of genetically altered algae.  Acres of bags floating along the low lying southern coast.  Harvest by flushing, reseed cleaned bags and repeat. It makes a great diesel fuel.  I will start with global maps and images on the web, looking for great low lying coastal region.  NASA has a project going, there has been demos.  Soon we will be seeing kits, amateurs with access to water can set up their own algae bags.  Popular with dairy farmers.