Coolant tank doesnt have a min/max fill level?

coolant tank on my nrg doesnt have a min/max fill level, although the haynes manual says the capacity says 1litre, and the ready mixed putoline is 1litre, shall i put it all in?

 

No, drain as much as u can. Put the putoline in until its half way up the expansion tank. Run the engine for 5 mins. Check level again when the engine has had time to cool, give it a good half hour. Has it gone down? If so add more... normally on expansion bottles the min and max mark is around half way up the bottle, i would fill yours to just above half to be safe and keep an eye on the temperature.

 

cheers buddy great help!