Citric Acid concentration

[TheDivrDwn]

Hey @Randy Holmes-Farley I was curious to know the concentration you recommend for citric acid bathing your pumps/equipment in? Not looking for cups to quarts measures, but the specific molarity or molality you're targeting?

 

[redfishbluefish]

Interesting request. I’ll give you a rough estimation on what I typically make up to clean equipment. I typically use ¾ to 1 cup of citric acid to one gallon of water (US measurements).

Assumptions
1 cup of citric acid weighs = 130 grams
Molar mass of monohydrate citric = 210.14 g/mole
1 gallon = 3.79 liters


So 130 g CA x 1 mole/210.14g = 0.619 moles

0.619 moles / 3.79 liter = 0.16 M

 

[Randy Holmes-Farley Verified Community Expert]

I've never used it. I've only used vinegar and hydrochloric acid. That said, concentration is not that important for dissolving calcium carbonate, and I think 5% by weight is a good concentration.

Diluted muriatic acid (hydrochloric acid) used is typically about 1 M and is faster to dissolve things than is 5% acetic acid (vinegar).

 

[Snoopy 67]

I have gone as high as 2cups/gallon.

 

[blasterman]

Its just acetic acid. At 1/5 calcium carbonate has no chance if soaked in a bucket.

I tend to avoid muriatic acid because it can splash and boil and have consequences for being in a hurry

 

[bubblemytip]

I think too much citric acid can lead to crazing on acrylic - has happened on my skimmer, so use vinegar for soaking skimmer body, but citric acid for the pump.