PrimoChill Opaque - Computer WaterCooling Show Coolant, Solid/Non-Transparent, Full Protection, Advanced User, PrimoPrep Included, Proudly Made in The USA (32oz/.9L)
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24 colors. Filter by family, or press Compare colors to see two to four side by side.
Tap two to four colors, then press Compare. Done goes back to choosing.
Why builders choose Opaque
PC Opaque is PrimoChill's solid-color show coolant. Every tube, fitting and reservoir reads as one flat, saturated color with no see-through depth, so a 16 mm tube and a full reservoir look exactly the same in person and in photos. It comes ready to pour in 24 colors, made in the USA, with a bottle of PrimoPrep in the box to get your loop ready for it.
Opaque hides the inside of the loop and shows one even color, in daylight or under studio lights.
No depth-dependent color shift, so thin tubes, thick tubes and the reservoir all match on camera.
Pre-mixed and pre-dyed. Nothing to measure and nothing to add.
A 2 oz bottle of PrimoPrep comes in the box to condition the loop before the fill.
Opaque is water-based and drains out cleanly when you want a new look.
Repeatable color from batch to batch, preservative-free and APE-free, and safe on plastics, rubbers, gaskets and acrylic.
Is Opaque right for your loop?
Works with
- Show builds and display machines run for sessions
- Copper, brass and nickel-plated blocks and radiators
- Acrylic, PETG, glass and PVC tubing
- Standard rubber gaskets and O-rings
- PrimoChill fittings (only the cap is coated, so nothing leaches into the fluid)
Keep out of an Opaque loop
- Machines that run around the clock
- Any aluminum part, including radiators and aluminum kits
- Silver or silver-plated parts, including kill coils
- Fittings coated on the inside, where the color touches the coolant
- Any other coolant, dye or additive, another Opaque color, or plain water
Running a high-pressure loop with micro-channel blocks? Opaque wears faster there, so a pressure relief valve in the loop is a good idea. The full compatibility list is on keepingit.cool.
Getting the most from Opaque
Opaque's color stays even in a loop that has been properly prepped. The included PrimoPrep and the steps below get it there.
Air works against the pigment. Pour slowly, cycle the pump on and off, and keep bleeding until the loop is free of bubbles.
Keep pump time under 8 hours a day, turn the system off when it is not in use, and run the pump as slow as your temperatures allow.
Look over the reservoir and tubes each day at first. If the color separates or collects anywhere, drain and rinse right away.
Never add water or anything else. A low reservoir gets more of the same color.
How long a fill lasts depends on pump hours, prep and your loop. A fresh fill around every six months keeps the color at its best.
Filling a loop with Opaque
- Clean every partNew blocks and radiators carry machining oil and flux. Clean the radiators with Rad Clean and rinse the blocks before anything goes together.
- Leak test on distilled waterRun the loop on plain distilled for 12 to 24 hours with only the pump powered.
- Run SysPrep for 48 hoursThen drain and rinse with distilled until the water runs clean. Loop already ran another coolant? Use System Reboot here instead.
- Run PrimoPrep for 72 hoursMix the included 2 oz bottle into 32 oz of distilled or DI water, circulate, then drain and rinse.
- Fill with OpaquePour slowly at a low pump speed, bleed until the loop is clear of air, and note the fill date.
Step-by-step guides: prepping a new loop and reconditioning a loop that ran coolant.
- PC Opaque, 32 oz (.9 L)
- PrimoPrep, 2 oz
Read the full care and warranty details
Please read all of this before filling your loop. Skipping these steps can void the warranty.
Opaque is made for show builds and experienced builders. For a machine that runs all day, Ice or Pure is the better pick. Like any custom loop, it needs regular maintenance and inspection.
Staining. Any colored coolant can stain tubing, acrylic reservoirs and blocks, and long use can make the staining permanent. How much depends on the color. PrimoChill does not replace stained components.
Color change in the first 48 hours. Opaque can change or lose color in the first 24 to 48 hours in a new loop. If that happens, drain the loop, flush it with DI or distilled water, and refill with fresh Opaque.
High pressure and micro-channels. High-pressure loops with micro-channel blocks break the coolant down faster. We strongly recommend a pressure relief valve in every loop.
Particle buildup. As with any opaque coolant, particles can collect in block micro-channels over time and slow or stop the flow. If you see any collection or separation, drain and rinse the loop right away. Running a loop after the coolant has separated can mean taking apart and cleaning every component.
Nothing else goes in. Do not add other coolants, additives, silver coils, water or another Opaque color. Any of them changes the formulation and can cause sludging or breakdown, and voids the fluid warranty.
Aluminum. Using Opaque with aluminum components, such as aluminum radiators, is strongly discouraged and voids the fluid warranty.
PrimoChill is not responsible for any hardware damage. Use at your own risk.
What buyers said
Left by people who bought this part here. Compatibility reports are the useful ones — if you installed it, say which board.
Questions people ask about this coolant
Answers specific to PC-OP32K-BCV. If yours isn't here, ask — we'd rather talk you out of the wrong part than sell you one.
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Ask us before you order
Send your exact hardware model and we'll confirm the right part before you spend $24.99 — or tell you honestly that this isn't the one.
Returns are accepted within 30 days and are easy to start in the support center. Unopened items can be returned for store credit with no restocking fee; other returns carry a restocking fee, higher for items that have been installed or used.