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

RyRy Paints uses masking fluid in almost every watercolor painting she makes. It’s such a simple tool, yet it makes a big difference in controlling highlights and preserving clean shapes.

If you’re curious about how RyRy Paints uses Winsor & Newton’s Art Masking Fluid and Permanent Masking Medium, you’re in the right place!

She’ll walk you through how they work, how she applies them, and the cool effects they can create in your artwork.

What Is Art Masking Fluid for Watercolor?

Masking fluid is one of the artist’s favorite watercolor tools. It helps protect areas that need to remain white, allowing painting to continue freely without worrying about losing the highlights.

Why Use Art Masking Fluid in Watercolor Painting

What the artist appreciates most about Art Masking Fluid is how easily it peels off. Once removed, the white paper underneath stays clean and bright.

That makes it perfect for sharp details, such as reflections in an eye or a sparkle of sunlight.

Benefits of Yellow-Tinted Art Masking Fluid

Winsor & Newton’s masking fluid has a yellow tint, and that small touch makes a big difference. When applied, the tinted color is easy to spot on the paper. It doesn’t mix into the paint—its purpose is simply to show exactly where the masked areas are.

How to Use Permanent Masking Medium with Watercolor

The Permanent Masking Medium works differently but is just as useful.

Permanent Masking Medium Stays on the Paper

Unlike masking fluid, this medium is never peeled off. It remains on the paper and becomes part of the painting. Instead of creating a crisp white, it leaves a soft resist effect.

Clear Appearance When Dry

This medium begins visibly, but once dry, it nearly disappears. It does not stand out like masking fluid. When the artist wants a gentler, softer highlight, this is the preferred choice.

Tools and Supplies for Using Masking Fluid in Watercolor

Here are the tools that help apply both products properly. It’s simple, but there are a few tricks.

Why Use Old Brushes with Masking Fluid

Masking fluid can ruin good brushes quickly, which is why the artist always uses an old brush assigned specifically for this task. A small container—about the size of a thimble—is used to pour a bit of masking fluid for dipping.

Handling the Texture and Smell of Masking Fluid

Masking fluid has a strong, sulfur-like smell, similar to latex. Its texture is rubbery with high surface tension. When brushed on, it often forms bubbles and sits on the surface in a slightly raised layer. This is normal.

How to Apply Masking Fluid and Masking Medium in Watercolor

Each of these products requires a different approach.

Tips for Applying Art Masking Fluid

When applying masking fluid, the artist often uses a bigger brush and applies it in a thick but controlled layer—thick enough to peel off easily, but not excessively heavy. The fluid is placed gently and not rubbed in.

Best Way to Apply Permanent Masking Medium

When applying the Permanent Masking Medium, a lighter touch is better. A generous but not overly thick coat works best. Too much medium can dry with a gray tint. A thinner layer dries clearer and performs as intended.

Wait Until Masking Fluid and Medium Are Fully Dry

Before adding paint, both masking products must be completely dry. This step is crucial.

Masking fluid looks nearly identical wet and dry, except dry fluid appears slightly matte. Permanent Masking Medium almost vanishes when dry, so it may be hard to see—this is normal.

Once everything is dry, the artist is ready to paint over them.

How to Paint Over Masking Fluid in Watercolor

Now comes the enjoyable part—painting over the masked areas.

Using High-Saturation Watercolor Over Masked Areas

The artist uses Winsor Green directly from the tube to achieve bold color quickly, mixing in a little water for flow. With a synthetic sable brush, color is gently painted right over both masked areas.

How Art Masking Fluid Resists Watercolor Paint

The masking fluid pushes the paint away. Because it has a rubbery texture, watercolor cannot stick to it. The artist loves this effect—it works beautifully for whiskers, tiny glints, lettering, or any detail that requires a crisp white highlight.

How Permanent Masking Medium Reacts to Watercolor

Permanent Masking Medium also resists the paint, but only partially. Some pigment lightly settles on the surface, creating a softer, more natural look. Unlike masking fluid, this medium remains on the paper permanently and cannot be peeled off later.

How to Remove Art Masking Fluid from Watercolor Paper

Once the paint is fully dry, the artist removes the masking fluid by gently rubbing with a clean finger or a soft eraser.

Tips for Safely Peeling Off Masking Fluid

Peeling reveals crisp, bright, untouched paper beneath. This method is perfect for windows, reflections on water, sharp highlights, and clean lettering.

Art Masking Fluid vs Permanent Masking Medium: A Comparison

Both tools are valuable, but each serves a different purpose depending on the desired effect.

When to Use Art Masking Fluid

• Creates very crisp, clean edges
• Peelable
• Best for bright highlights and fine 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

When masking fluid creates lines that feel too harsh, the artist softens them with a damp brush. With masking medium, some pigment can be lifted to lighten the area and create gentle transitions.

Creative Ways to Use Masking Fluid and Medium in Watercolor

Masking doesn’t have to be applied only to white paper. It can also be used on top of previously painted areas.

Masking Over Painted Backgrounds

For example, after painting a yellow-green wash, the artist adds masking marks to create blades of grass.

Masking Grass, Moons, and Cityscapes

The artist uses masking fluid for bold highlights—such as moons, bright windows, and city lights—while using masking medium to preserve softer highlights in grass or glowing windows.

After painting a darker layer (green, magenta, or mixed tones), the masked areas remain bright and visible.

Advanced Watercolor Masking Techniques

Layering creates dimension and dramatic effect.

Layering Paint with Masking Fluid

A typical sequence the artist uses:

• Paint a gradient sky

• Dry it with a blow dryer.
• Then  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 the artist used these techniques.

Lionfish, City Lights, and Sparkling Water

The artist masked parts of a lionfish before adding brown stripes.

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

Experiment with Masking in Realism and Abstract Art

Both mediums open up endless creative options. The artist loves 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. The artist uses both depending on the effect desired. Crisp highlights? The artist reaches for masking fluid.

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