I don't whether things in ZA are different to here in the UK, but we basically get two choices - blue and pink/orange. The important point is, don't mix the two! As long the system is flushed out between each fill you can freely use whichever one you want. They all do basically the same thing, so as long as you follow the instructions on the bottle and don't mix pink with blue, you'll be fine. Make sure to bleed the air out of the system after filling to prevent airlocks causing overheating.