Well, yesterday morning when I fired up the car, I got the COOLANT LOW message in the instrument cluster.

Opened up the bonnet and coolant level was indeed low. Off to a service station and topped up coolant. Thing is, I cant seem to make out where the max mark on the bottle is.

Anyhow, this morning before starting the coolant level was about 5mm lower than the level that I filled it to the day before.

Checked it again now when I parked the car. Must be about 2cm lower than the level filled to on yesterday morning.

I've looked around the engine bay and I can not see anywhere where the cooling system leaks coolant. Not a single drop on the floor after standing a while either.

Opened oil filler cap and luckily no "mayonnaise" in there.

Where could the coolant be going? Should I be concerned? I'll obviously be monitoring this closely.