How to Remove Hard Water Chalk Deposits from Darkroom Plastics?

Andre Noble · Dec 3, 2015

Hello,

I live in LA where the water is incredibly chalky you dont need to take mineral supplements if you drink the water.

This chalk depsoits from tap water coats my plastic darkroom measuring cups, grad cylinders, etc.

Is there a plastic-safe way to remove this chalk from the plastic or is the chalk permanently embeded?

Thanks in advance.

BrianShaw · Dec 3, 2015

I know the problem well but don't know of a way to remove without causing surface damage to the plastic... which only seems to make future build-up more likely, more quick to develop, and more difficult to remove. I haven't done so myself, but believe that water treatment and filtration may be the most viable countermeasure.

Jim Jones · Dec 3, 2015

Try ordinary vinegar. Photographic purists might prefer to use a working solution of stop bath.

BrianShaw · Dec 3, 2015

Jim... that's what my coffee pot manufacturer recommends. Way back when I worked in a diner and we used ice and salt -- lots of salt and swirling around -- to clean the carafes. But honestly, when they got too dirty we tended to accidentally break them.

Old_Dick · Dec 3, 2015

Walmart has a "cleaning" vinegar. I believe it is slightly more acid then the regular. Works for me, I'm on a well in NH, very high calcium and iron. I'm always cleaning with it. I use distilled water for my chemistry.

RobC · Dec 3, 2015

Yes acid will dissolve what is mostly calcium deposits. Vinegar, acetic acid and I would suggest any hardware store product for descaling kettles and the like.

Many years ago I lived in a very hard water area. When we moved here which a very soft water (acid) our kettle was heavily scaled with deposits from the hard water. Within a few weeks it had completely cleared of its own accord due purely to the natural soft water (which does have a small amount of minerals in it and will leave drying marks).

Old_Dick · Dec 3, 2015

Forgot to mention that it works as well or better then the more expensive products like CLR or Lime-Away.

Sirius Glass · Dec 3, 2015

I am close by you in Westwood. Use vinegar or Lime Away.

Andre Noble · Dec 3, 2015

hey Sirius Glass, do you have chalky water in Westwood too? Just wondering.

Ken Nadvornick · Dec 3, 2015

I grew up in the greater Los Angeles area with experience in two darkrooms there, and I've had some degree of success in the past with this product:

CLR Calcium, Lime & Rust Remover

Ken

Mainecoonmaniac · Dec 3, 2015

Vinegar works with boron

Jim Jones said:
Try ordinary vinegar. Photographic purists might prefer to use a working solution of stop bath.

I live in Davis, Ca and I use vinegar to remove boron and other minerals from shower and faucet heads. For me, my darkroom trays have years of accumulated stains. As long as it doesn't affect your work, I'd leave it. Besides you can't see your deposits on your darkroom plastics under a safelight .

Sirius Glass · Dec 3, 2015

Andre Noble said:
hey Sirius Glass, do you have chalky water in Westwood too? Just wondering.

No, not really. Eventually calcium will build up in the water in Santa Monica, Beverly Glen and Westwood, but I would not call the water chalky. I have never had a water or streaking problem processing film or prints.

Andre Noble · Dec 3, 2015

You guys in West LA are lucky then.

Thanks for the helpful replies everyone.

ColColt · Dec 3, 2015

We've got hard water in my area as well. Periodically, I give my coffee pot a white vinegar douche but haven't had problems with plastic graduates as I clean them within minutes of using them. The coffee pot gets more use and abuse.

kobaltus · Dec 4, 2015

Vitamin C or acidum ascorbicum better and faster clean my coffe pot than vinegar.

Fujicaman1957 · Feb 12, 2016

The cleaning vinegar is 5% acid vs 4% for regular vinegar

How to Remove Hard Water Chalk Deposits from Darkroom Plastics?

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