Lightobject.com Support Forum

I have a 80W Reci tube and the 600W chiller.

My question is how much coolant ?

Do you fill the chiller as recommended, start off with no coolant in the
laser tube and then wait for it to fill the laser tube with no air bubbles ?

Or, does the laser tube need to be filled when not in use... I would think
then the coolant would drain back into the chiller and overflow ?

I gave it a try... Looks like the chiller has the
capacity to maintain a full tube and circulate.

are you using water or some type of antifreeze...?

Distilled water, you can buy it anywhere...

Then, I add some "Red Line" Water Wetter.

It's basically a coolant additive for water jacketed
performance motors. Supposed to have no reaction
to metals, corrosion w/metals.

Since the laser is all glass & tubes, seams to work well.

With coolant running;

Normally coolant that used for automotive heat exchanger has the ability for corrosion protection and anti-freeze characteristic. But one thing different is that water in automotive is circulating at near boiling temperature, whereas water for cooling the laser tube is normally running around 20 C. This low temperature range around 20 C is suitable for microbiological growth, regardless using distilled water or not. Keep an eye on the water side inside the tube after some time.

Add some aquarium algacide that should stop the growth. You can get laboratory grade algaecide but it's mega expensive!

I've been using Distilled Water and the pink additive
on my 40w laser cooling system and don't see any
visible algae growth ????

It happens sometimes just keep an eye