@vkiiali and @speedster_101
always go for pre-mixed coolant. It happened with me some years ago. I bought coolant in which i had to add 50% water.
We added water but in 6-8 months, there came lots of engine noises which eventually resulted finally into lots of engine work in just 1 year of new zero meter Suzuki Alto
Culprit was our office "water", actually in my previous office area, there is shortage of water so they have done boring work(well water), This underground water gets filtered at our Reverse osmosis filtration plant of factory & finally comes in tap but even after that it is full of several minerals & organics,It is too high in calcium,magnesium & other salts.
so this boring water or well water destroy your coolant, radiator & ultimately your engine :(