27 Watercolor Octopus Ideas and Other Deep Sea Wonders

A watercolor octopus is one of the most satisfying things you can paint in a single afternoon: eight loose arms, a soft blobby head, and endless excuses to let the colors bloom and bleed into each other on wet paper. There is no wrong way for a tentacle to curl, which makes this the perfect subject for playing with pinks, teals and violets without worrying about getting it exactly right.

Below you will find 28 ideas, starting with a whole parade of octopuses in odd little moments (sipping tea, hiding in jars, wearing pearls) before heading deeper into the water for jellyfish, seahorses, a giant squid, and some genuinely strange creatures that most people have never tried to paint. Pick whichever one makes you smile first and have your paper wet before you start.

Start with the head: drop a rounded triangle of coral or warm pink onto wet paper and let it bloom softly at the top, keeping the bottom edge a little drier so it stays crisp where the arms begin. While that is still damp, pull eight curling lines downward with a fine brush, thinning each one as it tapers, and let two or three arms cross over each other for depth.

Paint the teacup last, once the octopus is dry, in a pale cream or dusty blue so it reads clearly against the body. The classic mistake here is making all eight arms the same length and curve, which flattens the whole pose, so vary the curls and let one or two arms droop lower than the rest.

If this is your first time painting an octopus, sketch the head and just two guide arms in pencil first, then build the rest by eye once paint is down. No teacup on hand to reference? A small circle with a curved handle reads instantly, no need for realism.

One tip for today: wet the head fully before adding color so the coral blooms on its own instead of looking painted-in.

Palette: Coral, Payne’s Grey, Cream, Dusty Blue

Painting an octopus tucked inside a glass jar is really an exercise in two transparencies at once: the glass and the water inside it. Paint the jar’s outline lightly in pencil first, a simple rounded rectangle, then lay a very pale wash of grey-blue only where the glass catches light, leaving the rest of the paper white for highlights.

Drop your octopus color inside the jar shape while that wash is still damp, letting pink or violet pool and spread so the arms look like they are pressed against the curved glass. Add a few darker navy lines along the jar’s edge last, to suggest the glass rim and base sitting on a surface.

Where this goes wrong is painting the glass too solid, which hides the octopus completely. Keep the glass wash thin and uneven, almost patchy, since real glass reflects unevenly too. No jar to look at? Any drinking glass on your table works as reference for the curve.

Try this: paint the jar first and let it dry completely before adding the octopus, so the two layers stay clean and separate.

Palette: Violet, Grey Blue, Navy, White

A kneaded eraser can lift back a soft highlight on the jar’s curved side once the wash dries, giving it a glassy shine without repainting anything.

Keep this one calm and let the octopus be the star rather than the pearls. Paint the head and arms first in a soft teal, wet-into-wet, letting the color pool heavier at the top of the head and fade toward the arm tips so the body has natural shading without any blending work.

Once fully dry, add the pearl necklace with small circles of white gouache or a white gel pen, spacing them slightly unevenly along a gentle curve across the front of the head, since perfectly even spacing looks stiff and mechanical. A tiny dot of grey beneath each pearl gives it just enough roundness to read as a bead rather than a dot.

The common mistake is cramming in too many pearls; six to eight is plenty for a necklace that reads clearly at a glance. If you do not have gouache or a gel pen, a thin mix of white acrylic works just as well for these small opaque dots.

One tip: wait until the octopus is bone dry before adding pearls, or the white will bleed into the teal and disappear.

You Will Need

• white gouache or white gel pen

Palette: Teal, White, Soft Grey, Navy

This is where you get to paint a whole little scene instead of a single creature, so plan the layout loosely in pencil first: octopus roughly in the middle or lower third, coral shapes rising around it like plants in a garden bed. Paint the coral first, in warm coral pink and soft orange, using simple branching shapes and a dry brush dragged upward for texture at the tips.

Once the coral is dry, paint the octopus over and among it in a contrasting teal or violet so it stands apart from the background rather than blending in. Let a couple of arms drape over coral branches to tie the whole composition together.

The eye level matters here: keep everything at the same gentle downward angle, as though you are looking into a tide pool from slightly above, which makes the coral read as growing upward rather than floating randomly. If dry brush coral feels tricky, dab a stiff brush loaded with thick paint instead for a similar bumpy texture.

Tip for today: paint coral in at least three different pinks so the garden does not look flat.

Palette: Coral Pink, Soft Orange, Teal, Navy

An octopus wearing an old brass diving helmet is a fun contrast of soft and hard shapes, so block in the helmet’s dome first with a pale wash of warm grey, leaving a bright highlight shape untouched on one side to suggest curved metal. Add the round porthole window as a small dark circle once that wash dries, with a thin rim of gold or ochre around it.

Paint the octopus body spilling out beneath the helmet in deep violet, letting the arms splay loosely below in all directions since this is the most expressive part of the piece. The helmet should look like it is simply resting over the head, not fitted tightly, so leave a little gap of color showing at the base.

Metal surfaces go wrong when painted perfectly smooth, so add two or three darker grey streaks across the dome for old brass character. No ochre paint on hand? A touch of yellow mixed into burnt sienna gets you close enough.

Quick version: paint just the helmet and head in ten minutes; the full forty-minute version adds trailing arms and bubbles rising from the porthole.

Palette: Warm Grey, Ochre, Violet, Navy

Picture this octopus as though it is carrying little glowing lanterns, each one a tiny jellyfish drifting near its arms. Paint the octopus body first in deep navy or indigo, kept fairly dark so the glowing jellyfish really pop against it later.

Once dry, paint three or four small jellyfish near the arm tips in pale glowing teal or soft yellow, bell shapes with a few thin trailing lines beneath for tentacles. Add a tiny halo of white gouache or a soft dry-brush glow around each jellyfish bell to suggest light radiating outward into the dark water.

The glow effect fails if it is too hard-edged, so soften the halo by wetting the paper slightly before touching in the pale color, letting it feather outward on its own. If gouache feels fussy, a very diluted wash of white watercolor dabbed gently works almost as well.

Tip: keep the background water a flat, dark navy wash so every glowing jellyfish reads instantly against it.

You Will Need

• white gouache

Palette: Indigo, Glowing Teal, Soft Yellow, White

This playful idea gives each of the eight arms its own tiny paintbrush, so start with the head and body in bright coral or pink, painted loosely and left to dry before adding any fine detail work on top. Curl the eight arms outward in a rough circle or fan shape, since this pose reads much more dynamic than arms hanging straight down.

Once dry, use a very fine brush or a pen to add a thin brush handle to the tip of each arm, with a tiny dab of a different paint color at the very end of each one, like a little palette of colors fanned across the paper. This is the fun payoff detail, so take your time and make each brush tip a distinct hue.

The mistake to avoid is making the brushes too long or too straight, which looks stiff against the curling arms; keep each one short and slightly angled to match its arm’s curve. No fine brush available? A fine black fineliner outlines the brush shapes just as cleanly once the paint is dry.

One tip: paint a tiny splash of color on the paper near one brush tip, as if mid-stroke, for extra charm.

You Will Need

• fine brush or fineliner for brush handles

Palette: Coral Pink, Teal, Violet, Soft Yellow

Give the octopus something to guard by painting a small wooden treasure chest tucked beneath its arms. Block in the chest first in warm brown, keeping the lid and body as two simple rectangular shapes, then add a few darker brown lines for plank edges once the first wash is dry.

Paint the octopus draped over and around the chest in deep teal or navy, letting two or three arms curl possessively over the lid and one arm dip inside if you leave the lid slightly open. A scatter of small gold dots spilling from the chest reads instantly as coins, no detail needed beyond simple circles.

Perspective matters here: keep the chest at a slight angle rather than straight-on, which makes the whole scene feel more like a candid glimpse of the ocean floor. If gold paint is not in your set, mix yellow with a touch of brown and a little white for a convincing metallic warmth.

Tip for today: let a few coins scatter outside the chest onto the sand below for a more natural, lived-in scene.

Palette: Warm Brown, Gold, Teal, Navy

This idea is really about color blending rather than any particular pose, so let the octopus shape be simple: a rounded head and eight loosely curling arms, sketched lightly in pencil first. The magic happens in how you lay down color, wetting the whole shape first and then dropping in coral pink at the head and glowing teal at the arm tips, letting the two bleed into a soft violet where they meet in the middle.

Tilt the paper gently while the paint is still wet to help the colors shift and blend naturally, which is what gives this piece its iridescent, shimmering quality rather than a flat two-tone fill. Once dry, a few tiny dots of white gel pen scattered across the body add a sparkle that mimics real iridescence.

This goes wrong if you rush the blending and the two colors stay separate with a hard line between them; keep the paper quite wet and work quickly. No gel pen handy? A toothpick dipped in white gouache makes fine sparkle dots too.

Try varying this next time with a pink-to-violet or teal-to-gold blend instead, same technique, entirely different mood.

You Will Need

• white gel pen

Palette: Coral Pink, Glowing Teal, Violet, White

Curl the octopus into a large spiral shell for a cozy, quiet ending to the octopus section. Paint the shell first, a simple spiral or clam shape in soft peach or cream, with a few curved lines following its natural ridges once the base wash dries.

Tuck the octopus inside, body in soft violet, with arms curled gently around itself rather than spread wide, since a sleeping pose reads best when everything feels compact and relaxed. Closed or half-closed eyes, just two small curved lines, finish the sleepy feeling instantly.

The common slip is making the shell too large and empty-looking, so let the octopus fill a good two-thirds of the shell’s opening, arms tucked snugly against its curves. If peach is not in your palette, a warm cream mixed with a touch of coral gets you there.

One tip: add a single tiny bubble drifting up from the shell opening, it sells the underwater stillness in one small mark.

Palette: Peach, Cream, Violet, Navy

Moving from octopuses to jellyfish, a whole bloom of them drifting together makes a dreamy next subject. Wet the paper broadly first and drop in several jellyfish bell shapes in varying sizes using soft pink, teal and violet, letting each one bleed softly at the edges while still touching the damp paper around it.

Once the bells are dry, add fine trailing tentacles beneath each one with a very thin brush, letting the lines wave gently rather than falling perfectly straight, since real jellyfish drift with the current. Vary the length of the tentacles between jellyfish so the bloom feels alive and uneven rather than a repeated pattern.

This piece can turn muddy if too many colors touch each other while still wet, so leave a little white space between each jellyfish’s wet bloom to keep colors distinct. If your thinnest brush is still too thick for tentacles, try the tip of a toothpick dipped in paint instead.

Tip: scatter a few tiny dots of white around the composition for distant bubbles and extra depth.

Palette: Soft Pink, Glowing Teal, Violet, Navy

The leafy sea dragon is one of the most delightfully strange creatures in the ocean, covered in leaf-like fins that make it look like drifting seaweed. Sketch its long curved body lightly in pencil first, since the proportions matter here: the snout is long and thin compared to the body, roughly a third of the total length, so measure that against your sketch before committing to paint.

Paint the body in warm olive or sandy gold, then add the leafy fin shapes along its back and sides in a slightly brighter green-gold, letting each leaf shape bleed just a little at its edges to feel organic rather than cut out.

Surround it with a few simple kelp fronds in deeper green, painted as long wavy strokes rising vertically, which also helps camouflage the sea dragon the way it would in real water. If gold feels tricky to mix, a straight ochre works as a simpler substitute.

Tip for today: keep the kelp fronds taller than the sea dragon itself so it looks tucked among them rather than floating in open water.

Palette: Olive, Sandy Gold, Deep Green, Navy

After the leafy sea dragon’s long body, the nautilus offers a calmer, more geometric subject built around its spiral shell. Lightly trace a spiral guide in pencil first, or trace around a round lid or coin to get the shell’s outer curve even, since a lopsided spiral is the fastest way for this piece to go wrong.

Paint the shell in warm cream and soft brown stripes following the spiral’s curve, leaving thin white gaps between stripes for the shell’s natural banding. Once dry, add the small tentacled head and body peeking from the shell’s opening in a muted grey-violet, kept simple since the shell is really the star here.

Light plays a big role with a glossy subject like this: imagine light coming from the upper left and leave that side of the shell paler, deepening the brown stripes slightly on the lower right for a believable curve.

No coin or lid to trace? Freehand the spiral lightly and loosely first in pencil, then erase and refine before inking it in paint.

You Will Need

• plate or lid to trace the spiral

Palette: Cream, Warm Brown, Grey Violet, Navy

Nudibranchs are basically nature’s excuse for unreasonably bright color combinations, which makes them perfect for a bold watercolor moment. Paint the soft, elongated body first in one saturated color, hot pink or electric orange, keeping the shape simple: a rounded teardrop with a slightly ruffled edge.

While still damp, add a contrasting color along the ruffled edges and down the back in small frilly protrusions called cerata, dabbing rather than dragging the brush so each little frill stays distinct and textured. These frills are where the real character lives, so do not rush this part.

Overworking the frills until they blur together is the main risk, so let each dab dry a little before adding the next one nearby if your paper is very absorbent. No neon or fluorescent paint in your set? Layer a bright primary color twice for extra saturation instead.

Tip: finish with two small antenna-like rhinophores on the head using a fine brush, just two short upward lines, to make it instantly recognizable as a nudibranch.

Palette: Hot Pink, Electric Orange, Lime, Navy

Palette: Violet, Glowing Teal, Deep Plum, Navy

Scale up for this one: a manta ray’s wide, flat body makes a striking shape when it fills most of the page. Sketch the wingspan first using a simple measuring trick, comparing the width of the wings to the length of the tail, roughly three to one, to keep the proportions convincing before any paint touches the paper.

Paint the top side in deep navy or charcoal, wet-into-wet, leaving the two wingtips slightly paler where they catch ambient light from above. Flip the underside pale cream or white if you show the ray banking to one side, which adds a nice contrast and a sense of movement through the water.

The gill slits and small cephalic fins near the mouth are easy to overdo, so keep them to a few simple thin lines rather than elaborate detail. If charcoal grey is not mixed yet, a touch of black into navy gets you there quickly.

Try this again later banking the other direction, or seen from directly below with the pale belly filling the whole page.

Palette: Navy, Charcoal, Cream, Teal

You Will Need

• white gouache

Palette: Near-Black Violet, Charcoal, Pale Yellow, White

Palette: Coral, Soft Peach, Teal, Navy

Palette: Deep Indigo, Navy, Glowing Teal, White

Palette: Pale Pink, Lavender, Navy, White

Palette: Pale Blue White, Lavender, Pale Pink, Navy

Palette: Sandy Tan, Warm Brown, Cream, Navy

Palette: Dark Maroon, Burnt Sienna, Grey, Pale Yellow

Palette: Teal, Soft Gold, Coral, Navy

Palette: Silver Blue, Charcoal, Pale Yellow, Navy

Palette: Deep Maroon, Near-Black Violet, Glowing Blue, Navy

Palette: Pale Pink, Lavender, Sandy Tan, Navy

What to Do Next

Pick whichever creature made you want to reach for your brush first, wet your paper, and let the color do most of the work. If you want more ocean subjects to pair with this list, the easy ocean watercolor animals and watercolor fish tutorials make a good next stop once today’s octopus is dry.

Frequently Asked Questions

What paper works best for a watercolor octopus?

Cold press watercolor paper around 140lb works best for a watercolor octopus. Its texture holds wet-into-wet blooms well, which gives the arms and head that soft, bleeding color these pieces rely on.

How do I stop the octopus arms from looking stiff?

Vary the length and curl of each arm instead of repeating the same curve eight times. Let two or three arms cross or overlap, and keep the lines thinning toward the tips for a more natural, trailing look.

What colors give that glowing, iridescent deep sea look?

Blend coral, violet and glowing teal wet-into-wet so they merge softly at their edges rather than staying separate. A few small white gel pen or gouache highlights added once dry finish the iridescent effect.

Do I need masking fluid or special supplies for these sea creatures?

Most of these ideas need only your usual watercolor kit, but a white gel pen or white gouache helps a lot for glowing jellyfish, anglerfish lures and pearl details. Masking fluid is optional for keeping highlights crisp.

How do I keep colors from turning muddy when blending several at once?

Work quickly while the paper is still properly wet and avoid overloading the brush with too many pigments at once. Let busier pieces dry fully between layers, such as the cuttlefish or vampire squid, rather than adding every color wet into wet.