I want to color water white/cloudy/milky, so that it disperses light nicely. I have tried to dissolve soap in it, which worked very well, but the dissolved particles sink down after half a day and the effect is gone.

Are there any better ideas than buying food color (since we're talking about a life hack)? The fluid should also not be prone to molding, which I guess will happen when milk is used.

  • 1
    Can the downvoters please comment on why they downvoted?
    – kamuro
    Commented Jul 13, 2016 at 14:42
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    No idea why the down votes, but I'm curious. What are you doing with this? Commented Jul 13, 2016 at 14:52
  • I want to use it for at least two projects in which I want a fluid to look like it is radiating light. The straight forward one is a jam jar standing on an insuspicious surface which has a (hidden) rgb led and an arduino in it. I realized this with the soapy water and got some nice reactions. The second one would be something that should resemble small laboratory vials that look like they have a radioactive substance in it, by lighting them with a green led. Those would then be fixed and the led would be inside the water but hidden from sight. Let's hope this works ;)
    – kamuro
    Commented Jul 13, 2016 at 15:10
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    Anti-freeze looks radioactive without lighting :) And if you had a blacklight, many clear liquids glow under it. Commented Jul 13, 2016 at 16:16
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    @Stan It might solve their problem, but it doesn't really address the question. :) Commented Jul 13, 2016 at 17:22

8 Answers 8


Anything you can suspend in water that will look white will be a particulate of some kind (like paint pigment). Any particulate larger than colloidal size will fall out of suspension over time. Dyes will stay dissolved (as food coloring will) but dyes don't have the property of reflection, so can't look white.

The best I can suggest is colloidal chalk, which is produced by a reaction between lime water and carbon dioxide. Children's chemistry sets used to include instructions on how to make lime water, and you can blow your breath through the solution to provide the carbon dioxide.

An alternative solution would be to find a way to recirculate the water, so that whatever you suspend (water color pigment, for instance) will stay suspended rather than settling out. An aquarium pump and airstone is one option. You will surely have trouble, over time, with algae growth that will turn your pretty white water green, brown, or reddish, but there are algicides you can add to the water to slow or prevent this (they're sold for fountains, to keep them from filling with pond scum, and for water beds).


Inorganic soluble cutting oil used in industrial machines such as lathes and mills. It's mixed with water, stays in solution as far as I know, and doesn't mold.


You could try adding something to milk to sterilize it. Household bleach may work, but may also turn it clear (bleach turns coloured things white, but I'm not cure if it turns white things clear). Campden tablets (sodium metabisulfite) as used by homebrewers for sterililising might be a better choice.

You didn't say what you need this for, so I don't know if it has to be a liquid or just look like a liquid. I have heard that food photographers will use PVA glue instead of real milk.

  • Thanks for the input. I wrote a comment on the question to clarify the use in response to the usage question. It needs to be liquid. But maybe pva glue is somewhat soluble in water (or another liquid).
    – kamuro
    Commented Jul 13, 2016 at 15:19
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    Based on the applications you mentioned, it appears to me that you could possibly add gelatine to your mixture so that it has some properites of solid and liquid and once set the particles cannot sink.
    – Dave
    Commented Jul 13, 2016 at 15:39

Commenting on another answer gave me the idea to use an anis spirit (ouzo, sambuca, pastis, raki) mixed with water. The ouzo-effect results in a milky solution which, according to the Wikipedia article, is very stable due to the small particle size in the range of microns and the chemical interplay. I will try this (and suggestions in the other answers) out and update the answer (comment on answers).

  • The alcohol won't be subject to mould or other similar problems that you'd have with organic actual milk or powdered milk.
    – Stan
    Commented Jul 13, 2016 at 16:57
  • I am not sure about that. The alcohol might not, but the sugar and other ingredients might be. I don't have any experience in this field. But if it rots away, I'll be sure to note it down here. First I have to get some pastis, though ;)
    – kamuro
    Commented Jul 13, 2016 at 21:39

The stuff only has to look milky; not be milky to achieve your goal.

When I shoot liquids for advertising that I want to glow (or look like they do) such as a glass of frosty beer or a jar of marmalade jam, etc, I put a reflector card behind the subject and let the light show through the liquid.

Using this technique allows me to vary the lighting in a very controlled way that mixing unknown substances don't. If your liquid stuff is too thick or too thin you won't achieve the effect you're striving for. All you have to do is slightly angle the reflectors for each test tube or flask in your set-up.

Product photographers have been doing this for years.

If you choose the colours for the card reflectors, you can get any colours you want sitting right next to each other. Green next to fluorescent red is easy to achieve this way without using coloured liquids at all. For white, use a white card. For blue, use a blue one, etc.

Trim the cards carefully so they don't show.

LED lights are adjustable but you'll find the stray light hard to harness. Different hues of stray light will mix giving you neutrals which will diminish your intended effect. You'll see the problems in the final shot.

If you were shooting functional props for motion pictures, your way would be necessary due to handling by the talent, angles for shots would be uncontrolled, and the lighting problems for that situation are difficult.

  • I appreciate your answer, especially from a photographic point of view, and I know the technique with colored reflectors, I first saw that in the YT video of Karl Taylor where he photographs the whisky bottle. Have never used it myself though. - The projects I'm having, however, are about the decorative purpose, so they should look nice in my flat and in the hand ;)
    – kamuro
    Commented Jul 13, 2016 at 21:43

Mica powder. I made a hallow key chain shaped like a milk carton with “milk” inside. I used baby oil and mica powder.


Another thing I have tried is porridge oats, or even the starch from pasta, spaghetti or rice. Add this to a bath of warm water or you can also add this to milk or simply add milk to water.


use white phenyle concentrate mixture of pineoil and alfrox 200 as emulsifier

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