How can I keep the water from freezing

I live in Edmonton Alberta Canada and it gets below minus 30 degrees Celsius here during the winter I keep my laser in my garage my garage is insulated but it does get pretty cold is there anything I could add to the water to stop it from freezing or even change to a different substance any help on this matter would be great

I use an aquarium heater in bucket and keep pump running.


Your choices are limited. In general, you can heat the water, put in antifreeze, drain and re-fill, or move the water to some place that doesn’t freeze. It’s not nearly as simple as keeping antifreeze in cars.

Heating the water and using the water to keep all of the cooling loop, including the tube, is one way. You have to provide enough heat, which depends on how cold the air is. That in turn depends on how good your garage insulation is. In the long run, you might have to put enough heat into the water to heat your garage. You could put blankets or some such over just the machine and water bucket to be able to use less heat.

Putting antifreeze in the water is a bad idea from the standpoint of laser operation. The things work best with distilled water. That is the only recommended coolant by the tube makers that I’ve ever found. The more stuff in the water, the harder it is on your power supply as it has to supply any leakage currents .If you’re not insisting on being able to walk out into the garage and start cutting, you could put in antifreeze, but flush it all out when you wanted to use the machine again.

You might get away with using some aquarium style water disconnects and moving the bucket into the above freezing house, draining and re-filling just the tube.


Some of LightObject’s chillers got a built-in heater. That’s probably the neatest solution for this problem.

Anyhow, I’d use a cooler (ice box) as reservoir and some aquarium heater and a thermostat to keep the temperature of the coolant above 5 °C. If the laser sits on a small cart/table with the reservoir below, you can cover the whole thing with a blanket to keep that little bit of warmth inside.

I’d heat the whole room up to about 15 °C (at least 10+ °C) before using the machine. Check if there is any condensation.

The built-in thermostats for aquarium use only go down to about 18 °C or so. I’d use a generic thermostat and a lower target to reduce the energy consumption a bit.

The pump would be always running. You could use a separate thermostat to turn it on when the ambient temperature drops below e.g. 7 °C.

If you build your own thermostat which controls both devices, you can make the pump control a bit smarter.


Late to the party, but I’ve only just joined the forum - So Hello everyone.

What I would do?..

  • The first thing is to have removable insulation for your tank AND your tube
  • As above, Deionized water only
  • Get a PAIR of aquarium heaters - They do fail! - I’d go for 2x ceramic 300W, and set to the lowest temperature, they will only be on for short periods if the tank is insulated.
  • You might want to use a secondary (smaller) pump if your water pump is a big boy! You only need to maintain a small flow. On the other hand, a larger pump will be adding energy to the system.

In addition…

  • You might want to place a mains “tube heater” with a frost stat under the laser, and a tarp over the setup - I have used a very similar system for years to keep a tortoise from freezing in the winter, however I use an electronic stat with PID, to manage the temperature accurately within 0.5C of 5C, and also have remote monitoring.
  • You might want to add remote temp and flow monitoring - nice little ESP32 project for peace of mind
  • As above, you could add an overriding thermostat to save power, but you are adding a failure point, and temperature is more or less unimportant provided that it is a little above 0C (32F in funny money :smiley: )
  • Another option - but consider fitting to / and removal from the laser tube - is the application of tracer heating cable. This is completely solid state and is typically used to prevent pipes from freezing (search self-regulating-trace-heating-cable). This would be a solid state system, no pump. However, tracers should work well in place of aquarium heaters along with a pump.

Since this thread is a year old What method did you opt for, Shawn, and was it successful?

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