Art Masking Fluid vs Permanent Masking Medium: Which to Use in Watercolor

I use masking fluid in almost every watercolor painting I make. It's such a simple tool, but it makes a big difference.

If you're curious about how I use Winsor & Newton's Art Masking Fluid and Permanent Masking Medium, you're in the right place! I'll walk you through how they work, how I apply them, and the cool effects they create.

What Is Art Masking Fluid for Watercolor?

Masking fluid is one of my favorite watercolor tools. It helps me protect areas I want to keep white. I can paint freely without worrying about losing the highlights!

Why Use Art Masking Fluid in Watercolor Painting

What I love most about Art Masking Fluid is how easily I can peel it off. Once I remove it, the white paper underneath is still clean and bright.

That's perfect when I need sharp details, like reflections in an eye or the sparkle of sunlight.

Benefits of Yellow-Tinted Art Masking Fluid

Winsor & Newton's masking fluid has a yellow tint. That small touch makes a big difference! When I apply it, I can spot it easily on my paper. It doesn't mix into the paint—just helps me keep track of where I've masked.

How to Use Permanent Masking Medium with Watercolor

Now, let's talk about the Permanent Masking Medium. This one works a little differently but is just as useful.

Permanent Masking Medium Stays on the Paper

Unlike masking fluid, I never peel this one off. It stays on the paper and becomes part of the painting. That means it won't give a crisp white, more like a subtle resist.

Clear Appearance When Dry

This medium starts off visible, but once it dries, it pretty much disappears. It doesn't stand out like masking fluid. If I want a gentler, softer highlight, this is the one I use.

Tools and Supplies for Using Masking Fluid in Watercolor

Let me show you what I use to apply both products properly. It's simple, but there are a few tricks.

Why Use Old Brushes with Masking Fluid

Masking fluid can ruin a good brush fast. That's why I always use an old brush just for this purpose. I pour a little into a small container—thimble-sized is enough—and dip from there.

Handling the Texture and Smell of Masking Fluid

This stuff smells! It has a strong, sulfur-like odor, kind of like latex. The texture is rubbery and has a lot of surface tension. When I paint it on, it sometimes forms bubbles and stays puffy. That's normal!

How to Apply Masking Fluid and Masking Medium in Watercolor

Now, let's apply the masking tools. I treat each one differently to get the best results.

Tips for Applying Art Masking Fluid

When I apply masking fluid, I often use a bigger brush and put it on thick. Not too thick, but enough to make it fun to peel off later! I don't smear it in—just let it sit and form a smooth surface.

Best Way to Apply Permanent Masking Medium

For the masking medium, I go lighter. I apply it generously but not too thick. If I go overboard, it can dry with a gray tint. A thinner layer helps it dry more clearly and work as intended.

Wait Until Masking Fluid and Medium Are Fully Dry

Before adding paint, I always wait for the masking fluid or medium to dry completely. This step is crucial.

I check that the masking fluid looks matte and no longer shiny. It basically looks the same, wet or dry. The Permanent Masking Medium almost vanishes when it's dry, so don't worry if you can't see it well.

Once dry, I'm ready to paint over them!

How to Paint Over Masking Fluid in Watercolor

Now comes the fun part—painting! Let me show you how both products resist watercolor.

Using High-Saturation Watercolor Over Masked Areas

I use Winsor Green from a tube so I can get bold colors quickly. I mix in a little water to help it flow. With my synthetic sable brush, I lightly paint right over both masked areas.

How Art Masking Fluid Resists Watercolor Paint

The masking fluid pushes the paint away. Since it's rubbery, the paint doesn't stick to it. I love this effect! It works perfectly when I paint whiskers, tiny glints, or lettering.

How Permanent Masking Medium Reacts to Watercolor

This one also resists the paint, but not completely. Some paint sticks a little. It gives a softer, more natural feel. But remember—it stays there! I can't peel it off later like the masking fluid.

How to Remove Art Masking Fluid from Watercolor Paper

After the paint is completely dry, I remove the masking fluid. I use a clean finger or a soft eraser and gently rub it off.

Tips for Safely Peeling Off Masking Fluid

Peeling it reveals crisp, clean edges. It's so satisfying! This is great for things like windows, glints on water, or clean lettering.

Art Masking Fluid vs Permanent Masking Medium: A Comparison

Both are great tools. But I do use them differently depending on the effect I want.

When to Use Art Masking Fluid

• Creates super crisp lines
• Peelable
• Best for bright highlights and tiny details

When to Use Permanent Masking Medium

• Stays on the paper
• Gives a soft, natural look
• Not as bright but feels more organic

How to Blend or Soften Masking Edges

If masking fluid lines feel too harsh, I use a damp brush to blur the edges. With masking medium, I can also lift some of the paint to get a lighter area.

Creative Ways to Use Masking Fluid and Medium in Watercolor

I also like using masking after painting a background. You don't always have to start with white paper!

Masking Over Painted Backgrounds

For example, I paint a yellow-green background first. Then, I go in with both masking products and paint blades of grass over the background.

Masking Grass, Moons, and Cityscapes

I use masking fluid for the moon and city lights. I also use the medium for little details in the grass and windows. After I finish painting a darker green or magenta mix over the top, the masked parts still shine through!

Advanced Watercolor Masking Techniques

Layering makes everything more exciting. Let me show you how I build up effects.

Layering Paint with Masking Fluid

Here’s what I do:

• First, I paint the sky with a gradient.

• Dry it with a blow dryer.
• Then I mix up some black and paint buildings right on top.

• The masked windows stay bright and sharp!

Create Natural Texture with Masking Medium

The masking medium doesn't block the paint completely, but it leaves a soft edge. I use it when I don't want my highlights to look too sharp or unnatural.

Watercolor Masking Examples and Results

Here are some real examples of where I used these techniques.

Lionfish, City Lights, and Sparkling Water

I masked parts of a lionfish before adding brown stripes. 

I did the same for a background wash to keep little sparkles in the water. The results are excellent once I peel off the masking fluid!

Experiment with Masking in Realism and Abstract Art

Both mediums open up endless creative options. I love using them for realism, abstract shapes, architecture, or fine details. Try them and see what suits your style!

Wrapping Up

Art Masking Fluid and Permanent Masking Medium each offer something special. I use both depending on the effect I want. Crisp highlights? I reach for masking fluid.

Softer textures? The medium works great. What kind of masking techniques do you enjoy using in your watercolor work? I'd love to hear how you make the most of these tools!