Why Do Show Coolants Lose Their Color? Understanding Flow, Shear, and Air Gaps in Custom Water Cooling Systems
PrimoChill Opaque/Vue and other Show coolants are popular in custom PC water cooling for their striking, solid colors and movement. But many users notice their coolant loses color or “falls out” (suspends particles drop out) over time, leaving the liquid clear or cloudy. This is frustrating and can ruin the look of a build. Let’s break down why this happens and how you can help your coolant last longer.
The Role of Coolant Flow and Shear
Show coolants are colored with tiny particles suspended in the liquid. These particles create the bold, solid look. When the coolant flows through your loop, especially at high speeds, a couple of things happen:
- Shear Forces: High flow rates create strong shear (friction) in the fluid, especially in sharp turns, tight blocks, and high-speed pumps. This intense movement can break down the bonds that keep pigment particles suspended. Over time, the colorant clumps or settles out, leaving clear or faded coolant.
- Turbulence: Fast-moving coolant doesn’t always flow smoothly. Turbulence, especially near pump outlets and in thin channels, can further disrupt suspension stability.
Why High Flow Isn’t Always Better
Many think more flow means better cooling, but with Show coolants, high flow rates do more harm than good for color longevity. The constant agitation accelerates particle fall-out. In most builds, slowing down your pump—even to half speed—won’t raise your temperatures much, but it will dramatically reduce wear on suspended pigments.
Recommendation:
Set your pump to a lower speed (e.g., 30–50% of max). This reduces shear and turbulence, helping your coolant stay opaque and vibrant for much longer.
Air Gaps: The Hidden Enemy
Air bubbles or gaps in reservoirs or distribution plates don’t just look bad—they hurt your coolant too.
- Turbulence from Air: When air is present in the loop (especially in the reservoir or distro plate), it creates chaotic flow patterns. This extra turbulence shakes up the coolant, making it harder for pigment particles to stay suspended.
- Surface Agitation: Air gaps expose the coolant to constant sloshing, which is another source of mechanical stress on pigment particles.
Tip:
Always bleed your system thoroughly after filling. Check for trapped air in reservoirs and distribution plates—top off until there’s no visible air gap.
Turn Off Your PC When Not in Use
Air bubbles or gaps in reservoirs or distribution plates don’t just look bad—they hurt your coolant too.
- **Running your PC 24/7 puts constant mechanical stress on your show coolant. Even with slower pump speeds, long run times mean more chances for pigment to fall out of suspension.
Simple Habit
Power off your PC when you’re not using it. This gives your show coolant a break and significantly extends its lifespan.
Key Takeaways
- High flow rates increase shear forces and turbulence, causing opaque coolant to lose its color faster.
- Air gaps in reservoirs or distro plates make turbulence worse, speeding up color fall-out.
- Slow down your pump to preserve your coolant’s appearance—lower flow is usually enough for good temps.
- Bleed air from your system fully after each fill.
- Turn off your PC when not in use for maximum lifespan.
- Lifespan of Show Coolants are 3-6 months pending on usage.
By considering these points, you can prolong the lifespan of your show coolants like PrimoChill Opaque and Vue, maintaining an attractive loop for a longer time. For the best durability and color retention, opt for clear or transparent coolants like PrimoChill Ice, PrimoChill Pure, PrimoChill True.