Plant roots are sensitive to temperature changes. Some, like garlic, require specific fluctuations while others like Wasabi will require lower, and highly maintained temperatures for their rhizomes.

The nutrient solutions within the hydroponic unit can become hot if your unit is set up outdoors in direct sun, or when your crop requires large indoor grow lights. So to achieve a well-maintained temperature in your hydroponic setup you will need a hydroponic water chiller.

Being able to control the solution’s temperature is important, as warm, or hot, water will directly affect how your plants grow. In some cases, it will kill your plant or allow the water to become a breeding ground for bacteria.

Also, warm water will hamper the absorption of nutrients. And pools of water also attract many other pests, which is bad news for your plants and for you.

While there are alternative methods to chill the nutrient solution in your hydroponic unit, for stable and reliable temperature readings, water chillers are fantastic.

After careful research, testing, and detailed comparison, we’ve put together an unbeatable resource to help you find the best water chiller for the money!

Quick glance at the best hydroponic water chillers:

Also Read:

Best Water Chillers For Hydroponics

Active Aqua AACH10/25/50/1000HP - Best Overall

LONDAFISH Aquarium Chillers Aquarium Fan Fish Tank Cooling Fan Marine 2 Fan

Amazon 

This unit is available in multiple rates of flow, with the entry-level providing a 1/10 HP. The entry-level unit also can remove heat at 1,020 BTU/h (British Thermal Units per hour).

This unit is ideal for reservoirs of around 10 - 40 gallons. And with a maximum of 10 PSI, this water chiller is able to keep up the pressure to circulate the water around the system effectively.

It is also Freon-free, which means no chemicals close to your nutrient solution while providing temperature control close to refrigeration levels.

While this might be useful for hydroponics it can also be used for saltwater applications. This is due to the fact the unit uses pure titanium evaporators, which are non-corrosive.

And the last major benefit is it is designed to be quiet when used. We’d highly recommend the Active Aqua AACH range created by Hydrofarm.

Pros

  • Designed for hydroponic use
  • Quiet operations
  • Great PSI and flow rates

Cons

  • Stock is difficult to source due to demand and multiple uses for aquaponics, brewing, and more!

LONDAFISH Chiller Fan - Best Budget Solution

LONDAFISH Aquarium Chillers Aquarium Fan Fish Tank Cooling Fan Marine 2 Fan

Amazon 

With few moving parts, the LONDAFIsh Chiller Fan is perfect for those hydroponic gardeners looking to keep costs low.

All the user needs to do is clip it on the side of the reservoir tank, plug in, and leave it alone.

While this unit doesn’t come with a thermal monitoring function that would allow for complete hands-off operation, it can reduce water temperature by 35°F - 37°F.

This isn’t a huge variation in temperature, but if you have your hydroponic setup in a grow tent with little ambient fluctuations, this is a perfect solution.

We’d highly recommend splashing out and purchasing a digital thermometer to check the nutrient solution is at the required temperature. Also, the fans will speed up the evaporation loss in your reservoir so keep an eye on water levels.

Pros

  • Cheap
  • Energy efficient
  • Basic and simple to install and use

Cons

  • No thermostat
  • Can cause issues if left unattended

CoolWorks Ice Probe - Best Small Reservoir Solution

YAMAHA P125 88-Key Weighted Action Digital Piano with Power Supply and Sustain Pedal, Black

Amazon 

This system uses a different method to cool the nutrient solution; advanced thermoelectric technology. In simpler terms, plug it into a controller and submerged the top rod into the water.

It is perfect for smaller grow setups as it can chill between 10 - 40 gallons with varying results.

At 10 gallons it can reduce temperatures by 6 - 8°F, 20 gallons by 3 - 4°F, and finally only 1-2°F with 40-gallon loads.

You can achieve better results by purchasing more units. It is also very quiet and easy to use.

Installation could be tricky as it can’t be completely submerged in the water, so it will need to be suspended.

How this will be accomplished is up to you. Also, to regulate temperatures you will need to purchase a control unit, which starts to increase the price. This being said, if you do just require it to constantly chill the reservoir, this is great.

Pros

  • Simple to use
  • Quiet operation
  • Can be scaled up with the addition of units

Cons

  • Not that simple to install
  • No thermostat regulation without additional purchases

Poafamx Aquarium Chiller 79 Gallon - Best Big Rig

Poafamx Aquarium Chiller 79Gal 1/3 HP Water Chiller for Hydroponics System Home Use Axolotl Fish Coral Shrimp 110V with Pump and Pipe

Amazon 

Developed for shrimp farming, the Poafamx Chiller is serious industrial strength water cooling technology.

With an integrated controller, it will allow you to set your desired temperature and just leave it to work its magic. Its compressor is also highly efficient, which will help save money on electrical bills.

It can be used for fresh and saltwater applications as well. Also, it is Freon-free.

The flow rate from the water pump, which is included, is 800l per hour.

And most importantly it is quiet and has multiple fans to ensure no heat build-up. Poafamx offer a year warranty with easy access to a customer helpline, which is great if you have any questions about the unit.

Pros

  • Solid packaged unit
  • Built-in controllers
  • Great customer service

Cons

  • Fairly high in price
  • Can be complicated for the novice user

BAOSHISHAN Aquarium Chiller - Best Brand Mention

BAOSHISHAN Aquarium Chiller 42gal 1/10 HP Water Chiller for Hydroponics System with Compressor Refrigeration Special Quiet Design for Fish Tank Axolotl Coral Reef Tank 160L

Amazon 

Designed for hydroponic use, this rapid cooling system will keep your nutrient solution at an optimal temperature of between 68-78°F for the best root development.

Unlike the other units on this list, this does use Freons, but they circulate safely around its chambers, which allows for quick cooling. And by using a full titanium coil, this unit is corrosion resistant and can be used for saltwater applications.

The BAOSHISHAN Aquarium Chiller also has two built-in fans, a temperature controller, and a monitor. It even comes with piping and a pump.

It is also incredibly quiet and reliable, which is music to our ears.

Pros

  • Good all-round package
  • Built-in systems
  • Easy to use

Cons

  • Misleading information on the product page

How We Select Our Water Chillers

When sifting through the hundreds of online options for the best hydroponic water chillers, there were a number of criteria we had to keep in mind.

Size

Before selecting any of these water chillers, you need to measure up how large your reservoir is and which unit could handle the load.

Too small, and the nutrient solution will never reach its optimal temperature. But this being said, too big isn’t a good idea either as it is a waste of capacity, budget, and creates unnecessary, ongoing, running costs.

To work out which right water chiller will work best, you need to add the volume of the reservoir, to the volume of the hydroponic channels, and buffer tanks. Then add on a capacity of 10% to ensure that you cover heat gain.

If you want to assist your water chiller, you can paint the reservoir a heat reflecting color. So, if it is black, paint it white.

Also, make sure the location of the reservoir is out of direct sunlight. If it is an outdoor unit, you can bury the water tank in the ground.

For those invested in keeping water chilling costs down, you can insulate the reservoir and hydroponic channels.

But as a rule of thumb, just by maintaining your hydroponic unit regularly, you can assist your water chiller to achieve its best results.

Maintenance of the chiller will also help.

Noise

Anyone who has lived with a noisy water pump can attest to the fact that noise levels matter.

Your hydroponic unit will most likely live indoors. With you.

With moving parts, fans, and electrical power supply boxes, a water chiller can become a noisy item in no time.

Make sure to read up about the decibels on each unit. Even a simple hum can turn a tranquil hobby into a nightmare.

Usability and Ease of Installation

User experience matters when installing a water chiller. If it is complicated to use on a daily basis, eventually you’ll leave it to do its own thing, resulting in poor temperature control.

Also, units without built-in controllers and temperature monitors will make getting the information you need harder. If you’re a hydroponic gardener who’s invested in a water chiller we can assume you want data.

If you’re more of an organic hydroponic gardener, a simple fan unit will do.

Temperature Control

A water chiller’s only function is to reduce water temperature. If you’re not happy with the range of capabilities of the unit, you’ll need to source a better system.

To achieve the best results for your plants’ roots you need to maintain a temperature range of 68-78°F. Depending on your crop you will need the water chiller to either maintain a higher or lower temperature, which will again affect your choice.

Materials Used

As mentioned, many of our choices use titanium for elements. Using titanium means it is anti-corrosive and in turn allows for the unit to last longer due to less wear and tear.

A generalization about materials used also indicates whether it is a quality item. The same is very true for water chillers.

Additional Features

When it comes to selecting water chillers, additional features are always welcomed, from automatic shut-off valves to temperature gauges.

Any additional features will help you maintain the optimal temperature with ease. This is especially true for those looking to be a bit more off-site.

After all, if you don’t work near your hydroponic unit, it’s impossible to check your water’s temperature during the workday.

Price

One of the major hurdles for hydroponic gardeners is the initial investment in equipment. From the pump, actual channels, air rocks, growing medium, net pots, and the plants themselves, hydroponic gardening can become expensive.

While it is fantastic to have a temperature regulator in your system, it’s not always needed, unless your unit is in direct sunlight, or your crop’s roots are temperature sensitive.

What Water Chiller Would We Buy?

While all these units are great, as we indicated, the Active Aqua AACH range ticks all the boxes for water chillers.

They are affordable, easy to use, have great pressure, quality materials, and more.

For those looking to elevate the production quality of their crop, investing in a great water chiller is a step in the right direction.

Also, water chillers can be used for multiple operations from aquatics to beer brewing. So, if you’re uncertain about investing just for hydroponics, you can use it for something else down the line.

At the end of the day, to achieve the best results from your hydroponic unit you need to be able to tap into data that will assist you, and a water chiller will give you that.