Tig Coolant--Water Soluble Oil Opinions

[The Metal Butcher]

Hi all. We picked up our first tig rig a while back and are trying to get some half decent coolant in it. The whole rig was bough for not much, and the miller stuff is too pricey for my blood. No real concern with freezing, just need something to keep the algae down. I bought distilled water, but I also have some water soluble cutting oil I use in the power hacksaw. It's been keeping the algae away for years in that thing, and it's no where near a closed system. Soluble oil should also lubricate the cooler pump. Thoughts?

tl;dr
I've read to use the real deal miller stuff, too pricey.
I've read to use RV antifreeze, I've heard it gels.
I've read to use regular anitfreeze, I've heard it clogs too (doubt it).
I've read to use bleach. Sounds hard on some metals.
I've read to use water soluble oil. Doesn't seem like a lot of disadvantages other than only being a mediocre biocide.
I've read to use water bed biocide. Seems like another good option.

I'd love to just use what I have on hand and not run out and buy anything if it won't cause any issues.

[MattiJ]

I wouldn't use water soluble oil but that's just me..

Kemppi is making world-class welding machines but is not in the "coolant business" and they recommend 20-40%(propylene) glycol in water OR any other proven antifreeze

I have been using straight distilled water for last 2 years as I forgot to add anything there and all the copper and tin seemed to have keep algae under control so far.
But I would preferably need antifreeze for winter, shop can get to freezing temps occasionally depending on heater setup.
Maybe next autumn..

[BigMike782]

I would buy coolant. I used private label stuff but I would not even think of water soluble oil or bleach. Automotive anti freeze is not intended for the very small passages in a TIG torch and can plug them.

[LKeithR]

We've run water-cooled tig torches for years and, yes, we tried at one time to go cheap on coolant. You
can run regular antifreeze (diluted of course) but over time it tends to gum things up. Never tried anything
else. We came to the conclusion many years ago that the Miller coolant is the best. Yeah it's a bit more
expensive but if you don't have to mess with it a lot it's well worth the extra cost...