only need one farmer to feed a small initial village,when you have solved puzzle 1, 2 and 3 and still have a small population
you still need only one farmer and he/she can research between crops, with only one farmer you may not even encounter the algae problem for a while, but with this version your farmer, once you can grow crops,

Ok have you enough tech points to buy farming level 2....... then your farmer with this tech will not fish anyway, with or without algae , he.she will search for coconuts and a small tribe can survive on them till the crops grow!!