coolant mixture

[ujimaflip]

I had a new rad put in last week (couple of holes - was beyond repair). Unfortunately it seems in fitting the rad, a joint some distance away was loosened. This means that I've lost a fair bit of coolant. I was miles from anywhere when I discovered this so I had to top up with tap water (I can already hear the sharp intakes of breath). How quickly do I need to get this drained and refilled - is there anything I can add instead? I've managed to fix the leak so I'm no longer loosing water. For info I added about 1.5 litres of water.
Help appreciated

[SamH]

excuse my lack of knowledge, but why should tap water be avoided?

[blackS2]

where is the problem??

but you should have enough G12+ in because of preventing corrosion...

f.e. you can draw half of the water in the coolant tank an refill with pure G12+