Best Water Chillers for Hydroponics: 2026 Buying Guide

Holds a reservoir at any setting from 6 to 30°C, reads to 0.1°C and remembers the setting after a power cut. Most growers set 18–20°C.

• Tanks up to 100 litres
• 6–30°C thermostat
• Titanium evaporator
• 9.2kg

• Nutrient solution never touches copper
• Over-current cut-out protects the compressor
• Quiet compressor, one-year warranty

Know before you buyNo pump or hose is included, and it puts the heat it takes out of the water into the room around it, so give it clear air.

The pump Hailea pair with the HC-100A. It moves 1,000 litres an hour, the top of the chiller’s flow range.

• 1,000 L/h
• 1.4m head
• 12W
• Submerged or inline

• Ceramic shaft for fresh and salt water
• Clip-on filter hoods keep debris out
• Built for continuous running

Know before you buyThe HX88 comes in eight sizes: choose the HX8810 for the HC-100A. Rinse the filter hoods whenever flow drops.

Feed pipe with a white outer layer that reflects heat and a black inner layer that blocks light, so solution warms less on its way to the plants.

• 13mm bore
• £1.30 a metre
• 30m roll £39.95
• Blocks light

• Less algae inside the line
• Also made in 19mm and 25mm for main feed lines

Know before you buyIt slows the heat the solution picks up on the way. It will not cool a tank on its own.

Reads water temperature to ±0.5°C and nutrient strength in one dip. Check the tank’s real temperature before you buy a chiller.

• Temperature ±0.5°C
• EC 0–19.9 mS/cm
• IP67
• Replaceable electrode

• Arrives calibrated with batteries fitted
• Earns its keep as an EC meter afterwards

Know before you buyIt gives a spot reading, not a log. Read the tank at the end of the light period, when it is warmest, every day for a week. If it never passes 22°C, you do not need a chiller.

A chiller cools the water but adds no oxygen. An adjustable air pump does that job, and cool water holds more of it.

• 78–3,600 L/h
• 8 models
• Adjustable output
• 1 to 8 outlets

• Quiet, with an internal muffler and rubber feet
• Dial the air up or down to suit the tank

Know before you buySite it above the water line, so solution cannot siphon back if the power goes off.