Don’t use algecides that contain copper. Or at least when I check for minerals copper doesn’t even register.
FYI, normal pool testing kits don’t check for copper to the level that you need.
I studied this in depth and came to the conclusion there are easier ways to obtain potable water than using pool water. Its fine for washing, cleaning and such. But not for consumption. Especially since without electricity the pool will rapidly become a green blob. JMHO
This lists a number of very good filters http://www.pleasanthillgrain.com/berkey_light_big_berkey_water_filter_british_berkefeld_portable_purifier.aspx