Best CPU Reservoir For Custom PC Water Cooling In 2020

Creating your custom water-cooled is a big step to take if you want to become a PC hardware enthusiast. Now, we’re not saying it involves any sort of rocket science, but you need to know your stuff. A lot of elements play an important in creating the perfect custom loop. Things like pumps, brackets, CPU blocks, GPU blocks, radiators, and fans all play their respective roles.

However, the most important component is a great CPU reservoir. The name itself is quite self-explanatory. In geography, a reservoir is defined as a large natural (or artificial) lake used as a source of water supply. The same concept applies here, just on a smaller scale. A reservoir stores the water or coolant for your loop. A pump handles the job of directing the flow of water.

You need to figure out what size of the reservoir you need, and what shape as well. This will depend entirely on your case size, and how much space you want to fill. There are a lot of brands out there that you can pick from. Fortunately, we’ve narrowed down the list for you. With that said, these are five of the best CPU reservoirs for custom water cooling in 2020.

1. Thermaltake Pacific DIY Reservoir/Pump

Unrivaled Performance

  • Perfect for larger builds
  • Excellent construction
  • Strong D5 pump
  • 5-speed adjustability
  • Anti-vibration brackets
  • Lacks RGB lighting

416 Reviews

Capacity: 300ML | Pump Included: Yes | RGB: None | Material: POM+PMMA

Thermaltake is one of the top brands when it comes to high-performance watercooling. Subsequently, we can expect high-end performance and great build quality from them. Thankfully, Thermaltake is yet to disappoint us on this part. The Pacific DIY Adjustable D5 Pump/Reservoir combo is proof of that.

On this list, you’ll notice that some of these reservoirs come alongside the pump. This is not uncommon and seems to be an ongoing trend. The water cooling community largely follows trends like this anyway. However, it’s quite an efficient solution. You don’t have to separately set up the pump or the reservoir. That’s because Thermaltake does all the work for you.

This Pacific DIY reservoir has a capacity of 300ml or 0.3 liters. That’s more than enough for most full-tower cases. It comes with its own bracket, so it saves us a bit of hassle. Because of the bracket, you can set this up either horizontally or vertically. That will come down to personal preference. It uses the standard G1/4″ threads. Because of that, most standard fittings should work just fine.

The D5 pump is excellent, and it’s also highly regarded as one of the best. It has 5-speed adjustability and can pump at a rate of 1135L/hr. That type of performance and speed gives excellent flexibility and versatility. It even has a noise-reducing aluminum housing. Apart from that, you get 2 years of warranty straight from Thermaltake.

The tank is made up of heat-resistant acrylic. We’re not worried about build quality in the least. The only thing lacking here is RGB, which may or may not matter to you.

2. Corsair Hydro Series XD5 Reservoir

Extravagant Design

  • Perfect flow balance
  • Eyecatching aesthetics
  • Easy to install
  • Near silent operation
  • Proprietary Corsair lighting control

383 Reviews

Capacity: 330ml | Pump Included: Yes | RGB: Yes | Material: Acrylic

Corsair is known for its excellent PC components and peripherals. They are one of the top manufacturers when it comes to mice, keyboards, headsets, and much more. Recently, they have been trying their hand at making custom water cooling components. The XD5 RGB Pump/Reservoir is an excellent first attempt.

The pump in here is the premium Xylem D5 PWM pump. It delivers an impeccable flow balance for a custom loop. We are huge fans of the design of this thing. The black exterior combined with the industrial-esque design gives it a unique look. It easily looks twice as expensive than it is.

It has a capacity of 330ml, which is surprising for the size. However, once you take a closer look, it is apparent that this reservoir is big in the depth dimension. This is not something we see every day, as reservoirs larger than 300ml are usually bigger. The Corsair XD5 is comically small for its capacity, and we mean that in the best way possible.

Of course, this can’t be a Corsair product in 2020 without some RGB. It has ten top-mounted RGB LEDs that give some flair to the design of this thing.  The lighting can be customized if combined with a Corsair RGB controller. We wish Corsair would open to the door to third-party controllers at this point.

It has a rubberized mounting system, which reduces vibrations and noises. After all, want your custom loop to be quiet and look good in the end. Corsair even includes a 24-pin PSU jumper bridge, so you can drain and fill your system with ease. They have thought about everything here, that’s why we recommend it so highly.

3. IronBuddy Water Cooling Reservoir

Ultra-Durable Pick

  • Stands out from the crowd
  • Superb construction
  • Versatile and flexible
  • Perfect for ATX systems
  • No plugs for ports

28 Reviews

Capacity: 300ml | Pump Included: No | RGB: None | Material: PMMA

A lot of water cooling reservoirs can end up looking the same. Sure, water cooling looks unique in and of itself. However, when everyone has the same type of reservoir, you can’t help but notice the similarities. People often have the same bends as well, so how do you stand out from the crowd?

Well, IronBuddy hopes to answer that question. Their answer lies in the form of the IronBuddy Water Cooling Tank Reservoir. With an extremely approachable name like that, we can expect this to be a great companion to our custom loop. If you think the same, well you aren’t wrong in the slightest.

Let’s talk about the materials first. The tank uses aluminum construction, and the cylindrical body uses PMMA. The commercial name for this thermoplastic is acrylic. However, it’s not the same thing. We won’t go into details, or we’ll be sitting here all day. Just know that this thing is durable. It uses standard G1/4″ connecting threads.

It has six of those thread holes, which means it’s easy to find a flexible way to put your build together. Versatility and flexibility are two things we love about this reservoir. The cylindrical tank is more than adequate for water cooling. The Helix or DNA shape adds to the uniqueness of this reservoir. It isn’t functional in a useful way, but it looks quite different.

Combine that with the aluminum finish, perfect size for ATX systems, and durability, and we have ourselves a winner. The only downside is that it doesn’t come with any plugs for the holes you don’t want to use. That’s a major oversight for such a great reservoir.

4. ZJchao Acrlyc Water Tank

For ITX Computers

  • Unconventional design
  • Perfect for smaller systems
  • Affordable price
  • No mounting hardware
  • Not compatible with some tubes

52 Reviews

Capacity: 200ml | Pump Included: No | RGB: None | Material: Acrylic

Just because you have a small mATX or mini-ITX case doesn’t mean you have to miss out. In fact, many smaller cases that have a custom loop end up looking even better. However, it’s considerably harder to manage a loop inside a small case. It is certainly doable, but we won’t lie and say that it is easy.

With that said, the ZJchao Acrylic Water Tank can make things a bit easier in your life. It’s an acrylic tank, so you can’t go wrong there. It’s not going to leak, so that’s most of its job fully accomplished. You can use standard G1/4″ fittings with those threads. The construction is surprisingly solid overall. While this is intended for smaller cases, it’s still an adequate size for an average system.

However, its not all roses with this reservoir. First off, it doesn’t come with any mounting hardware. That’s a bit disappointing considering the unconventional square shape. The corners are quite sharp, so be careful with it. Also, the holes are a bit small if your tubes have an inner diameter of more than 10mm.  But why does it earn a spot here then?

Well, the first reason is that the right person could find the perfect use for this. If you are looking for something unconventional for a small case, this is it. The second reason is the price, as this is one of the more affordable reservoirs on this list.

5. BXQINLENX Water Pump Tank

Entry-level Option

  • Exceptional value
  • Long lifetime
  • Lots of accessories
  • Sup-par pump performance
  • Looks awkward in ATX builds
  • Quality control issues

45 Reviews

Capacity: 86ml | Pump Included: Yes | RGB: None | Material: POM

BXQINLENX is a Chinese brand that makes a lot of custom water cooling components. While the brand name isn’t easy to pronounce, the products themselves are more approachable. Their 86ml also happens to be the best value on this list, and it’s perfect for an entry-level loop.

This reservoir from BXQINLENX is another one of those that uses a pump combo. It has a capacity of 86ml and pumps at a speed of 158.5GPH (600L/H). This reservoir is perfect for the average custom closed loop. Apart from that, it uses standard G/14″ threads both for the input and output. The working life is rated at about 50000 hours.

It consumes 19W of power and is rated at 12V of DC voltage. It has a ceramic shaft and ceramic housing along with a length of 110mm. Furthermore, prevents any hard particles from entering the pumps. Other than that, it has ceramic bearings, a graphite sleeve, and very quiet operation. An interesting part about this one is that it is submersible in water.

While this is a good entry-level pump/reservoir combo, we won’t recommend it for higher-end builds. This is mainly due to quality control issues. The provided barbs aren’t that great either. It does get the job done, but know that it doesn’t exactly deliver the best performance

Ace Luke


Ace Luke is a Washington Accord certified computer engineer with a keen interest in gaming and reviewing computer hardware since childhood.