This category holds pumps for custom liquid cooling loops in PCs, for builders who assemble a loop from separate parts rather than buying a sealed kit. The range includes pumps from Alphacool, EK Water Blocks, Laing, Aqua Computer, Bitspower and Barrow. Most loop pumps follow either the D5 or the DDC design.
How to choose a water cooling pump
Pump type. D5 pumps are usually larger, move a lot of coolant and run quietly at low speeds. DDC pumps are smaller and develop higher pressure, which suits restrictive loops with several radiators and blocks. Check which of the two a model is based on before you plan the layout.
Flow and head pressure. Flow rate tells you how much coolant moves per hour, and head pressure tells you how well the pump pushes through resistance. A single CPU block and one radiator need little of either. A loop with a GPU block, several radiators and quick-release fittings benefits from a pump with more pressure in reserve.
Speed control. Many pumps can be regulated through a PWM signal from the motherboard, and some come with their own controller and software for monitoring speed, flow and coolant temperature. Running a pump slower is the simplest way to cut noise once the loop is bled.
Reservoir and mounting. Some pumps are sold as a bare unit, while others are designed to bolt onto a reservoir or a pump top. A combined unit saves space and simplifies filling the loop, but it fixes your layout. A separate pump gives more freedom in a tight case. Check the thread size and port positions against your fittings.
Noise and vibration. A pump is the one moving part inside a closed loop, so its hum can be heard in a quiet system. Decoupled mounts or rubber dampers reduce the vibration that travels into the case panels.
Pump brands we carry
- Laing: the German maker behind the original DDC pump, which many other manufacturers use as the basis for their own pump units.
- Aqua Computer: a German specialist known for pumps with software control and sensor monitoring, such as its Aquastream and D5 Next series.
- Alphacool: a German water cooling brand that sells pumps alongside a large catalogue of blocks, radiators and fittings for the same loop.
- EK Water Blocks: a Slovenian company focused on custom loops, with pumps and pump-reservoir combinations designed to match its blocks.
- Bitspower: a Taiwanese brand best known for fittings and acrylic reservoirs, including mounting tops that take standard pumps.
Also in our range: Barrow.
Frequently asked questions about water cooling pumps
Do I need a separate pump for PC liquid cooling?
You need a separate pump if you are building a custom loop. Sealed all-in-one coolers already have a pump built into the block or radiator, so nothing extra is required. A custom loop circulates the coolant only when a pump is fitted, and it cannot work without one.
What is the difference between a D5 and a DDC pump?
A D5 pump generally offers higher flow and runs quietly, while a DDC pump is smaller and delivers higher pressure. The D5 is a common choice for large loops where low noise matters, and the DDC suits compact builds or restrictive loops. Both can be controlled by speed, so the final choice usually comes down to available space.
Can I run a liquid cooling pump without coolant?
No, a pump should never run dry. Many models rely on the coolant to lubricate and cool their bearings, and even a short dry run can damage them. Fill the reservoir first and power the pump only when it has liquid to draw in.
Do I need two pumps in one loop?
Most loops work well with one pump. Two pumps are sometimes fitted for redundancy or to raise pressure in very large loops with many radiators and blocks. If you do run two, they should sit in the same loop, ideally the same model, and each needs its own power and speed control.
