OBSERVE · UNDERSTAND · ACT

What are your plants telling you?

A leaf tells part of the story. Look at the plant, its new growth and the aquarium around it.

Observe my aquarium ↓

Observe · understand · act

Your aquarium has a story to tell.

A leaf changes colour. A film appears on the glass. Start with what you can see, then connect it to what has changed in your aquarium. Choose a photo to read its explanation below.

01

Look closely

Where did it start? Old leaves, growing tips, glass or wood? A close photo and the date help you compare the next changes.

02

Connect the clues

Think back: new plants, a brighter lamp, a missed maintenance day? Timing is often more useful than colour alone.

03

Take one clear step

Choose a measured first action. Record it, keep the rest of the routine steady and watch new growth rather than expecting an old damaged leaf to recover.

What do you see?

Click one symptom to read its explanation below.

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

OBSERVE · UNDERSTAND · ACT

Your observations, explained.

These are working possibilities. Compare the texture, location and timing before changing the aquarium.

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Bare lower stems

Lower leaves fall while the upper portion remains fuller.

Why it may happen

Shade from a dense canopy or ageing stems can contribute. A nutrient problem is only one possibility.

What to check

Whether the lower area is shaded and whether several species decline at once.

What to do first

Thin the canopy gently, space stems and replant healthy tops where appropriate for the species. Avoid simply extending the lighting day.

What improvement looks like

Healthier new side shoots and less loss from newly planted stems.

Read the source ↗

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Older leaves turning yellow

Yellowing begins mainly on mature or lower leaves.

Why it may happen

Ageing, shade and nitrogen limitation can look similar. Pale tissue with greener veins raises other possibilities, including magnesium.

What to check

New versus old leaves, existing nutrient inputs and nitrate trends rather than a single reading.

What to do first

Remove only failing tissue. Review lighting and nutrition together; correct a documented shortfall gradually.

What improvement looks like

New leaves develop normally; old yellow leaves may not recover.

Read the source ↗

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Very pale new growth

Young leaves are unusually pale, sometimes with greener veins.

Why it may happen

Iron availability can be involved, but colour varies by species, lighting spectrum and viewing angle.

What to check

Compare in neutral light and check whether the pallor persists as the leaf matures. Review pH and the complete nutrition routine.

What to do first

Keep a dated photo of the same shoot. Avoid adding iron repeatedly just because a water test reads zero.

What improvement looks like

Later leaves mature with a more normal colour.

Read the source ↗

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Holes and damaged edges

Small holes or patches of dead tissue, sometimes edged in yellow.

Why it may happen

Potassium limitation is a possibility, alongside physical damage, grazing and deterioration of old leaves.

What to check

Do new holes appear on intact leaves? Observe animals and compare where the damage starts.

What to do first

Protect damaged plants from mechanical stress and review existing potassium inputs before adding more.

What improvement looks like

New leaves stay intact. Existing holes do not close.

Read the source ↗

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Leaves becoming transparent

Leaves soften, turn translucent or disintegrate after a change.

Why it may happen

Some plants replace emersed leaves when submerged. Transplant stress or a rapid environmental change can also cause leaf loss.

What to check

Planting date, recent temperature or water changes, and whether the crown or rhizome remains firm.

What to do first

Remove decomposing leaves gently and leave a firm, living base in place. Keep conditions steady instead of repeatedly uprooting it.

What improvement looks like

New submerged growth emerges. A soft decaying base calls for a closer assessment.

Read the source ↗

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Little or no new growth

Few new leaves or shoots over the observation period.

Why it may happen

Slow species and non-injected tanks can grow slowly without being unhealthy. Shade, limited carbon, nutrition or root stress can also constrain growth.

What to check

The species’ normal growth, time since planting and the light actually reaching it.

What to do first

Compare weekly photos. Match the plant to the setup before increasing light or fertilizer.

What improvement looks like

Sustained new growth at a realistic pace for the species.

Read the source ↗

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Twisted young leaves

New leaves are crumpled, small or distorted.

Why it may happen

The pattern is not specific to calcium. Unstable growth conditions, carbon supply, mineral balance or physical injury may be involved.

What to check

Whether the distortion follows a recent change and affects one shoot or several plants; review the source water and remineralization.

What to do first

Keep conditions stable and document new growth. Avoid adding calcium or trace elements without checking the water and existing inputs.

What improvement looks like

Later shoots unfold normally; already distorted leaves may remain so.

Read the source ↗

Illustrations of typical appearances. Colour and texture vary; they cannot confirm an identification.

How to recognize it

Soft or buried rhizome

An epiphyte’s thick horizontal stem is buried, softening or losing leaves at its base.

Why it may happen

Anubias and similar rhizome plants need the rhizome exposed. Burying it can promote rot; softness also warrants checking the plant’s condition.

What to check

Separate fine roots from the thicker rhizome. Is it firm and exposed, or soft and covered?

What to do first

Expose the rhizome and attach the firm living portion to suitable hardscape. Remove decaying tissue carefully; do not try to repair rot with fertilizer.

What improvement looks like

A firm base and new leaves or roots; continued softening needs reassessment.

Read the source ↗

Give yourself time to observe

A steadier routine. A clearer picture.

Understand the aquarium, not just the symptom.

Give yourself time to observe

A steadier routine. A clearer picture.

Light: intensity and duration are different.

The timer controls how long the lamp runs. The dimmer, lamp height, tank depth and shade affect the light reaching a leaf. A long day does not compensate for a shaded plant; a strong lamp can demand more carbon and nutrients than the tank supplies. Tropica suggests 6 hours daily during the first three weeks, then a gradual increase toward 8 hours. Treat this as a starting routine, not a diagnosis.

Tropica · Read the source ↗

Maintenance removes sources of instability.

Remove uneaten food and decaying leaves. Siphon debris from the surface without uprooting the whole tank. Maintain filter flow and gently rinse clogged media in removed aquarium water; avoid replacing all biological media at once. Use a repeatable water-change routine suited to the animals and substrate, with conditioned water of compatible temperature and chemistry.

Nutrients, carbon and plant growth work together.

A planted aquarium can contain measurable nitrate and phosphate without an algae outbreak. Starving every nutrient may weaken the plants. Conversely, unnecessary extra doses can accumulate. Compare existing inputs, growth and water measurements over time. Healthy new leaves matter more than repairing old holes; damaged tissue usually stays damaged.

A simple observation plan

  1. 01

    Today

    Take a full-tank photo and a close-up. Note affected surfaces or leaves, your light settings and the latest change. Remove loose debris and check equipment.

  2. 02

    Over the next 7 days

    Keep a steady routine and record one deliberate adjustment. Compare the speed of recurrence on the same cleaned area. Avoid piling treatments together.

  3. 03

    Over 2–4 weeks

    Compare new leaves and the spread of the problem. Slow plants may need longer. If deterioration continues, reassess with dated photos and measurements instead of doubling doses.

Need another pair of eyes?

Send a clear close-up, a full-tank photo, the aquarium’s age, light settings, CO₂ setup and recent water measurements.

Contact Sousleau →
Sources and further reading

A visual resemblance is a clue. Aquarium algae names often describe an appearance, not a laboratory-confirmed species.