Inhibitor and biocide packages are rated for roughly twelve months. This is the annual service that resets the clock — done properly it takes an evening, and it is the difference between a loop that still photographs well at year three and one that gets torn down.
Shoot the reservoir, a tube run and any block you can see through. Compare against the photo you took at fill. Note anything that has shifted — colour, clarity, deposits at low points.
This is the only diagnostic you get. If something changed, you want to know before you flush the evidence away, because it tells you whether this is a routine service or a prep failure to correct.

Keeping It Cool is the technical library of PrimoChill. Products ship from primochill.com.
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