I just went to Amazon to pick up another bag of citric acid and found that it's $40 for the same bag I paid $15 for in January 2021. Guess I'll switch back to vinegar and just keep an eye on the price for a while. Even if I wanted to buy a 40 or 50 pound bucket (which I'm not going to do), it would still only bring the price down to about $5/lb, close to double what it used to be for five pounds.