Why is my plant melting?

 

WHAT IS 'MELT'?

Understanding the plant melt phenomenon is crucial for aquarists. The Eriocaulon sp. above is a classic 'plant melt' case: its leaves have lost colour and turned slushy and transparent, and the whole plant is on the verge of dissolving.  This phenomenon can be alarming, as healthy-looking plants suddenly deteriorate. 

Plant melt involves the leaves of aquatic plants losing color, turning slushy and transparent, and ultimately disintegrating. 

In this example, even the new leaves in the center have melted, so it is too late to save the plant.

90% of the time, melt happens due to Transition Stress.
It mostly happens in new tanks (or very mature ones).

Think of it as the plant struggling to adapt and scavenging anything it can get from its older leaves, 'eating itself' in a way. If it succeeds, new, adapted leaves emerge. If it fails, the whole plant might dissolve in as quickly as two days.

Causes of Plant Melt

Transition Stress

Transition stress, the primary cause of plant melt, occurs when plants in new tanks experience significant environmental changes. These changes can include variations in water parameters, lighting, and nutrient availability. The stress from these changes can lead to a breakdown of the plant's structure as it tries to adapt to its new environment.

WEAK STOCK

Plants from different shops may look the same but can vary significantly in health. It is the same reason serious dog owners prefer to get a puppy from a trusted breeder. A plant grown, transported, and stored in good conditions has more stored energy that allows it to adapt to a new tank more easily. 

EMERSED TO SUBMERGED Transition

Most aquatic plants are farmed emersed (with leaves above water) as plants grow more efficiently with better access to light / CO2. After planting in a new tank, they must adapt to submerged conditions. For many plants, this involves shedding all their emersed-grown leaves. 

This change from immersed to submerged in a tank without injected CO2 is extreme: available CO2 drops from around 400ppm (parts per million) in air to about 3ppm in water. As ~50% of plant mass is carbon, this is a huge deal.

CYCLING / AMMONIA Levels

In a newly set up tank (with a nutrient-rich aquasoil), the level of ammonia can be high enough to melt plants unless properly cycled. Uses of ADA Amazonia (in the past) used to experience plant melt as a rule, unless the soil was cycled for at least 2 to 3 weeks prior to planting.

In the picture above, we see slow and natural deterioration, not melt. As a general rule, damaged leaves do not heal, unlike say our skin. Plants channel their energy towards growing new leaves instead.

In a mature tank, plant melt can occur due to slowly deteriorating levels of nutrition: clogged CO2 diffuser, reduced flow from a filter that has not been cleaned for many months, depleted soil without regular fertilisation.

The outward melt may happen suddenly, but the underlying weakness probably developed over months, before reaching a tipping point.

7 PATHWAYS TO AVOID MELT:

Buy Healthy Plants

They should generally feel firm, with bright white (vs. yellow) roots. Leaves should feel sturdy rather than soft.

Ensuring Good Water Flow

Use an appropriately sized filter to provide good flow- this increases oxygen and carbon dioxide levels, especially in tanks without injected CO2.

Adjusting CO2 Levels

If using injected CO2, tune up the levels when adding new plants. This will make more food available to plants and help them transition.

Performing Proper Water Changes

Regular Water Changes involve siphoning the residue from the substrate. This removes algae triggers and reduces the competition for oxygen, carbon dioxide, and nutrition.

Lowering Temperature

Lower the temperature (to around 22/23 Celsius). This will slow metabolism and reduce oxygen and carbon dioxide demand during the transition to the new tank.

Planting Strategically

Plant in smaller, less-crowded bunches. This allows better water flow around individual plants, less overcrowding, and better access to light.

Providing Fertilizers

New plants have undeveloped root systems and cannot feed from the substrate, but they can still draw nutrients directly out of the water. Folks holding off dosing in new tanks are not helping their plants acclimate. Dosing should start from day 1.

 

Above: It is also common for new tanks to have diatoms, which is the brown stuff on the edges of the leaves and the brown 'cotton wool' mass on the substrate. It is sometimes confused with with plant melt. Diatoms generally disappear naturally after the tank gains biological maturity.

Additional Tips for a Healthy Tank

Monitor Water Parameters

Check water parameters such as pH, ammonia, and nitrate levels regularly to ensure they are within safe ranges. Stable water conditions reduce stress on plants. 

Maintain Equipment

Regular maintenance of filters, cO2 diffusers, and other equipment ensures they function efficiently and provide a stable environment for plants. 

Introduce Plants Gradually

Adding plants in stages rather than all at once allows for better acclimatization and reduces the risk of widespread melt. 

Observe and Act

Regular observation of plants can help identify early signs of stress or melt. Acting quickly to address issues can save plants before they deteriorate entirely. 

Choose Suitable Plants

Select plants known to thrive in the specific conditions of your tank. Some species are more resilient and adaptable than others.

People Also Ask

Can plants recover from melting?

In most circumstances, though, it is normal for a few leaves to melt on newly added plants. The plants will regenerate themselves provided the aquarium maintains the ideal conditions for their growth.

How to stop plants from melting?

In this case, the best course of action is to give the plant plenty of nutrients and stable water conditions to grow back over time. To allow the plant to concentrate on new growth, you can cut off all of the leaves at once or prune them one by one as they melt.

Conclusion

Preventing plant melt requires understanding its contributing factors and taking proactive measures to ensure a stable, healthy environment for aquatic plants. Aquarists can minimize the risk of plant melt and enjoy a thriving aquarium by selecting healthy plants, maintaining good water flow, adjusting CO2 levels, performing regular water changes, and providing appropriate nutrients. 

Regular monitoring and maintenance are not just tasks, they are a commitment to keeping your plants healthy and preventing sudden deterioration. By staying vigilant and acting promptly, you can ensure the well-being of your aquatic plants.