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keepingit.cool

Cooling,
documented.

Chemistry, dilution tables, prep sequences and service intervals for every PrimoChill fluid and kit. Not the marketing pass — the numbers we build to.

25
years mixing fluid
87
documented build steps
16
fluids and preps covered

Not sure which fluid you need?

Two questions — new build or existing system, showcase or daily driver — and get the exact fluid and prep sequence.

Not sure which prep you need?

Two questions — what you are prepping and whether you want the kit — and get the right bottles, in the right order, at the right dilution.

The loop

Every bottle has a place in the circuit.

Coolant leaves the reservoir, gets pushed through the blocks, sheds its heat at the radiator and comes back. Each prep treats a different part of that path — which is why running them out of order does very little.

Fluid colour
Sky Blue SX
Water-cooling loop topology and prep coverageThe pump drives coolant up to the radiator, where it sheds heat, then across to the CPU block, then the GPU block, then down into the reservoir, which feeds the pump again. Rad Clean treats the radiator on its own before assembly, for a one hour dwell. SysPrep and PrimoPrep are both circulated through the whole loop — SysPrep first, for twelve to twenty-four hours, to lift manufacturing debris, then PrimoPrep for seventy-two hours to settle the pH ahead of the permanent fill.PumpCPU blockGPU blockReservoirSysPrep · 12–24 hwhole loop — lifts manufacturing debrisPrimoPrep · 72 hwhole loop — settles pH before the fillRadiatorRad Clean1 h dwell
SysPrepWhole loop · circulate 12–24 h

The everyday whole-loop pre-treatment. 15 ml into one US gallon of DI or distilled water, circulated for a minimum of 12–24 hours, then drained and rinsed. It clears what the blocks, tubing and fittings carry out of manufacturing so your coolant is not the thing cleaning them.

Before the first fill

Nothing in this loop shipped clean.

Machining swarf in the block fins, flux and solder debris in the radiator, bending lubricant on the tube. Your coolant finds all of it on day one — and the fluid is the first thing people blame when the loop goes cloudy at week three.

Assembled loop with clear acrylic blocks and brass fittings
Machining swarfBlocks

A 0.25 mm fin channel does not need much to block. Open a new block and look before it ever sees fluid.

Brazing fluxRadiators

Sits in the tube ends from the factory. The number one source of blocked block fins in a first build.

PlasticiserSoft tubing

Leaches out of clear flexible tube over weeks. This is the clouding people see at two to six months.

Bending lubricantHardline

Handling oil and bending lube go straight into the coolant on day one unless the tube is wiped first.

Drain the first flush into a clear bucket and look at it against a white background. It is the most persuasive argument for prep anyone will ever show you.

The fluid line

Eight bottles. Four different forms.

Ready to use, concentrate, additive, base. Getting the form right matters more than getting the colour right — a concentrate poured neat is not a coolant, and an additive on its own is not one either.

Start here
The prep line

Four bottles. Four different jobs.

People reach for the wrong one constantly. Short version below — each opens the full chemistry, dilution table and dwell time.

New to the game

Never built a loop before?

16 guides, from the first radiator flush to the twelve-month service. Tools listed up front, nothing assumed, no video required.

Ask us anything

The support desk answers in build terms, not ticket terms.

Send a photo of the loop. We'll tell you what the residue is and which bottle fixes it.

Answered already

PrimoChill

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

Guides
Fluids

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