Corsa 2020 coolant capacity

[paul21paul]

Hi

I have an issue with the coolant in my 2020 sat nav premium 1.2 turbo The colour is dark brown /black. I've asked a local garage and he says it just the antifreeze colour Ive Never seen that colour ever before though. It is not oily to the touch just the normal antifreeze slippy and there is no sludge inside the expansion bottle to suggest oil mixing. Anyone else had this?? thinking of changing coolant but after trawling for hours cant find anything apart from its a Lobrid coolant???? any one know the capacity of the cooling system and any guide to purging it after refill Much appreciate any help thanks