Niskin bottles: simplest pure sample
-- degradation? : not huge problem as long as standard treatment for all samples
-- volume? : depends on what you're looking for (qPCR: a lot, high-conc HABs: prob not that much)
filter + pump as a way to get eDNA?
-- peristaltic/vacuum
-- Syd and Robin's eDNA needs ~80L
-- syringe that pulls water thru filter? not big enough scale
-- sterivac / c-vac?