What kind of coolant is recommended for WAJA Campro 1.6

Hi ,
I have query about the coolant use for WAJA Campro Engine, can some1 tell me what type of coolant should I use, I bouhgt a bottle cost rm5.90 which stated save for aluminium part mix abit of water, got people say must use battery water but some1 also said cannt use else the radiator will get corropted and leak. Last but not least my coolant need to top up quite often but the workshop said no leaking , what is the reason ? pls advise! Thanks !

thks,
Max