Loop coolant life

[CONSOLE_BUTCHER]

in my loop now is some mayhems distilled water, been in there since july last year. There is also two silver mayhems kill coils in that have been there since the loop started running.

Is it 1 or 2 years that it typically lasts?

I also checked my gpu block for any build up and there is nothing, except for some white speckles in the parts where the water doesnt flow.

 

[Undesirable]

No universal way of knowing for sure with each and every individual setup. It depends on several factors such as the type of coolant used (which you've told us, but I have no idea how kill coils affect the longevity of the fluid), the contamination level of your loop (stubborn flux still in rad?, cleaning kit used, or just rinsed?) and as demonstrated recently, whether UV lights are being used and which type they are. Keep checking every so often, as you have done.