At first I thought, KITEC.
On hydronic flooring manifolds there is a return manifold with balancing valves and flow meters. At lest on the ones I have inspected. They are sold electro mechanical devices or in this case clear vial which allow the owner or technician to see the condition of the liquid/water in the closed loop system.
Scoot examples how the liquid in beer is filtered for particulate and colorization of ales.
Martin’s post, “Looks like some nasty water in the flow meters” is one indication the system should be further evaluated by a licensed hydronic heating professional.
The clear potable water in the image I posted has discoloration. The source of water is an artesian well. There was no water filtration system prior the water entering the home. Big mistake because filtration removes soluble and insoluble mineral particulate. PH and acidity can be balanced.
What is causing the potable water discoloration in the Flow Meters. A break down of the tubing and fitting material for the water flowing through the loop I suspect.
Sorry members if I am not expressing myself correctly or precisely. I hope someone with more expertise reads the thread.