“………Citric acid... Isn't that vitamin C?.......”

No but both are found in citrus fruits. (yeah, I had to look it up )

https://www.fooducate.com/app#!page=...B-AB4E18ED0BE3

“…….I wonder if you added a couple nozzles, a water pump, and a livestock water heater if it would work even better?......

I think you just described a Jet Wash Ryan.

Keeping it warm would help….all I had was a small tank heater I used to keep it above freezing a couple of mornings.

Dave over at the machine shop told me the caustic solution is still available and I’ve hears of guys using a 55 gal drum with a ring heater to make a poor mans’ hot tank. The problem is getting rid of the solution after you’re done or it gets to the point where it’s not working anymore.

I’ve used vinegar to de-rust stuff in the past and the smell gets pretty intense and unpleasant (to me anyway). It’s also more expensive than the citric acid. The citric acid doesn’t have near the smell and what you smell mostly is kind of lemon scented. Basically when you’re done de-rusting what you have left over is rusty un-sweetened lemonade.

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