“Tropical fish” describes many species with very different bodies, fins and patterns. A butterflyfish does not look like an angelfish, and neither should be drawn like a betta or blue tang.
The best place to begin is with one particular fish and one clear reference. For this tutorial, choose a colorful reef fish photographed from the side. A butterflyfish, angelfish or tang will give you a readable silhouette and bold patterns without too much overlap.
I am going to approach this as a 15-minute sketchbook study. The time limit is not a test. It simply keeps the drawing focused on what makes your fish distinctive instead of getting lost in every scale.
The first two minutes: choose what matters
Spend the opening minutes looking rather than drawing.
Ask yourself:
- Is the body long, round or vertically compressed?
- Is the forehead curved or steep?
- Does the mouth project forward?
- Which fin changes the silhouette most?
- Is the tail broad, forked or nearly transparent?
- Which color marking would identify the species from a distance?
Choose two or three observations to carry through the drawing.
For a butterflyfish, it might be the tall body, pointed mouth and dark band through the eye. For an angelfish, it could be the triangular profile and extended fins.
A clear photograph will make these decisions much easier. My animal drawing reference article explains how I choose images with readable poses and enough detail.
Minutes two to five: draw the complete silhouette
Begin at the fish’s mouth and follow the upper edge of the head into the back.
Continue towards the tail, watching for where the dorsal fin interrupts or extends beyond the body. Then return to the mouth and follow the lower edge through the belly towards the tail.
Use direct marks. When your first line misses the observed edge, place another after looking again. Those thought lines can stay. They show the changes you made while finding the fish.
Do not turn the body into a generic oval. Look for the species-specific changes:
- A compressed body may rise steeply above the eye.
- A tang may have a more continuous curved profile.
- A butterflyfish may narrow sharply towards its mouth.
- An angelfish may extend much farther vertically through its fins.
At the end of these first marks, the drawing should already resemble your chosen species in silhouette.
Minutes five to seven: connect the fins to the body
Find where the dorsal fin begins along the back and where the anal fin begins beneath the body.
On many tropical fish, these fins contribute significantly to the overall shape. They may extend the fish upward and downward, continue nearly to the tail or taper into long points.
Draw from the attachment area outward rather than beginning with the decorative edge. This keeps the fins connected to the body.
Next, add the tail. Watch how the narrow tail base opens into the larger fin. The upper and lower edges may not mirror one another, especially if the fish is turning or the tail is moving.
Add the pectoral fin near the gill cover. It may be partly transparent, so a few directional lines can describe it without enclosing the entire shape.
Minutes seven to nine: place the face
The eye is often prominent, but its position matters more than its size.
Compare it with the mouth, forehead and gill cover. Some tropical fish have a dark band running through the eye, which can make its exact edge difficult to see.
Place the eye within that larger marking rather than treating it as an isolated circle.
Add the mouth by observing the upper and lower edges. Avoid adding a general smiling line. Tropical fish mouths vary from small and rounded to long and pointed.
Then look for the curved edge of the gill cover behind the eye. One firm change in direction may be enough to describe it.
Minutes nine to twelve: draw the pattern before the scales
Bold color patterns often identify a tropical fish more clearly than its scale texture.
Look for:
- Vertical bands
- Horizontal stripes
- Dark patches
- Spots near the tail
- Color changes around the face
- Contrasting edges on the fins
Draw these markings as areas moving across the body. Pay attention to how they bend over the fish’s surface.
A vertical stripe should not feel pasted onto a flat side. Its edges may curve as they cross the rounded body or continue into the fins.
If the pattern does not land where you expected, add a new edge after observing again. Keep the first one as part of the search rather than stopping the entire drawing to repair it.
Minutes twelve to fifteen: add color, value and selected detail
If you are working in color, begin with the largest areas.
A yellow body, black band and blue fin are more important than tiny shifts within individual scales. Allow colors to overlap, break apart or leave areas of paper visible.
If you are drawing in pencil or ink, translate the colors into different values. A bright yellow section may remain open, while a black marking becomes a dense area of tone.
Add scales only where they help describe the body. A few visible rows near the center may be enough. Let them become smaller, broken or absent as the body turns.
My tutorial on how to draw fish scales explains how to follow the fish’s surface without covering it in a chain-mail pattern.
Finish by strengthening a few areas:
- The eye
- The mouth
- The darkest body marking
- The base of an important fin
- An overlap near the tail
- A small shadow beneath the fish
Stop when the pattern, fins and body work together. You do not need to make every section equally detailed.
Drawing an angelfish
An angelfish is a good subject if you want to work with a strong vertical silhouette.
Notice how the dorsal and anal fins extend above and below the body. The trailing edges may taper into long points, making the fish appear taller than it is long.
The vertical bands should travel through the body and into the fins rather than stopping at the body’s edge.
Keep the mouth and eye relatively small. The extended fins and compressed body should remain the dominant features.
Drawing a butterflyfish
Butterflyfish often have deep bodies, pointed mouths and bold markings.
Begin with the slope from the forehead towards the mouth. Then observe how the dorsal and anal fins continue the body’s rounded or angular profile.
Many species have a dark band through the eye and another marking near the tail. These areas can disrupt the fish’s outline or confuse the location of the features, so compare them carefully with the photograph.
A few clearly placed markings will make the species recognisable before you draw any scales.
Drawing a blue tang
A blue tang has a broad, compressed body with a relatively small mouth and clearly shaped tail.
The dark pattern across the body is one of its most recognisable features. Observe its exact direction rather than treating it as a general decorative shape.
Let the pattern follow the body’s surface and meet the surrounding blue rather than enclosing it with the same dark outline everywhere.
The yellow tail creates a strong visual contrast, so give it enough size and space in the drawing.
If your drawing looks like a generic fish
Return to the observations you made in the first two minutes.
The body may need to become taller, shorter or more angular. The mouth may need to project farther forward. A dorsal fin may need more height, or the tail may need a different width.
Then check the pattern. If you invented stripes, spots or colors rather than following a particular reference, the fish may have lost its identity.
Do not solve the problem by adding more scales. Adjust the silhouette, fins or largest marking with new thought lines. Those features will have a greater effect.
Drawing tropical fish from an aquarium
An aquarium gives you the opportunity to watch the same fish return to similar positions.
Instead of trying to finish one drawing while the fish moves, place several small studies across the page. Draw the fish when it turns sideways, then begin another when it changes direction.
You might capture:
- A complete side view
- The tail bending during a turn
- A front view of the mouth
- A pectoral fin moving
- Two fish passing one another
- Reflections across the glass
These incomplete drawings can give you a better understanding of the fish than one highly controlled study from a photograph.
If you enjoy the flowing fins of aquarium fish, my betta fish drawing tutorial approaches the subject through the contrast between a compact body and moving fins.
For more species and beginner tutorials, explore my complete guide to drawing fish.