Encyclopaedia
Cryptocoryne cordata var. blassii
Cryptocoryne cordata var. blassii
Cryptocoryne cordata var. blassii: an elegant dark-leaved variety of C. cordata with bronze-brown leaves and a deep violet-red underside. Superb for midground layouts. Light: Low to medium.
Share
Check out Cryptocoryne cordata var. blassii on Atlarium
22 - 28 °C
5.5 - 7
Freshwater
Low to Medium
Low - High
35 cm
20 cm
1 - 10 dKH
Species description
This botanical variant grows primarily in the southern regions of Thailand, colonizing sandy and muddy banks of slow forest streams and swamps. It thrives under the shade of tropical forest canopies in waters characterized by low salt content but rich in natural organic acids, which keep the environment acidic and dark. It belongs to the Araceae family. Taxonomically described as Cryptocoryne cordata var. blassii, it represents a defined geographical variant within the cordata complex.
Care, breeding and tankmates
It prefers soft to moderately hard water (KH 1-10 dKH) and a pH between 5.5 and 7.0. Water temperature must remain stable in the range of 22°C to 28°C; sudden thermal or chemical shifts can induce leaf melt. It is subject to Cryptocoryne melt if introduced into immature aquariums or during drastic pH swings. If leaf loss occurs, keep the tank stable and wait for the rhizome to produce new shoots.
Geographic Origin and Distribution
This species originates from: Southern Thailand.
Origin
Plant profile
- Placement
- Midground
- Botanical form
- Rosette
- Growth
- Medium
- Substrate
- High
- Column fertilization
- Recommended
- Root fertilization
- Recommended
- Trimming
- Occasional
- Propagation
- Runners
- Sensitivity
- Moderate
- Layout role
- midground focal point
This species is ideally placed in midground to background of the aquarium. Its growth habit allows it to blend naturally with surrounding hardscape or other plants. When planted in small groups, it creates a cohesive and visually pleasing bush. Ensure it is not completely shaded by larger overhanging plants.
Cryptocoryne cordata var. blassii features striking reddish-purple leaf undersides. Its rosette growth pattern is typical of the genus, creating a dense crown of foliage. The distinct leaf shape and coloration make it stand out in the aquarium. It is sensitive to sudden parameter changes.
The growth rate of Cryptocoryne cordata var. blassii is generally moderate. Under lower light, it will grow slowly, but adding CO2 and moderate lighting can increase its pace. It steadily produces new leaves from its rosette once it has adapted to its environment. Patience is key, as it may take time to establish.
Cryptocoryne cordata var. blassii requires a deeply enriched substrate environment to fully display its striking leaf coloration and maintain long-term health. Planting it in a 3-inch bed of specialized aqua soil or clay-based substrate ensures its creeping rhizome and thick roots can properly secure themselves. The root network acts as the primary feeding mechanism for the plant, making the regular addition of root capsules essential for providing the iron and trace minerals necessary for vibrant growth.
While primarily a root feeder, it still benefits from regular water column fertilization. Dosing a comprehensive liquid fertilizer ensures that micronutrients are available. Be careful not to overdose, as excessive nutrients in the water column can promote algae on its slow-growing leaves. A balanced approach is ideal.
Root fertilization is crucial for the optimal development of Cryptocoryne cordata var. blassii. Providing a rich soil substrate or regularly inserting root tabs will yield the best results. Strong root feeding promotes larger, more robust leaves. It also makes the plant more resilient to environmental fluctuations.
Trimming should be done carefully by cutting old or decaying leaves near the base. Avoid pulling or uprooting the plant, as it has a delicate and extensive root system. Regular maintenance to remove dying leaves will keep the plant looking fresh and prevent rot. Only trim what is necessary.
Propagation is easily achieved through the natural production of runners. The mother plant will send out runners through the substrate, forming new plantlets. Once these plantlets have developed their own roots and a few leaves, they can be separated. You can carefully cut the runner and replant the new specimen.
Like many in its family, Cryptocoryne cordata var. blassii is prone to 'Crypt melt' when parameters suddenly change. Variations in temperature, lighting, or water chemistry can cause it to shed its leaves. However, the rhizome usually remains healthy. If melting occurs, leave the roots undisturbed and new leaves will soon emerge.
Its layout role is primarily for Colorful midground accents. The dense foliage and unique texture provide a natural transition between different zones of the aquascape. It is highly versatile and works well in both Nature Aquarium and Dutch styles. Its enduring presence makes it a reliable staple.
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
Related species
Recommendations grouped by close relatives, companion choices, and similar care.
Variants and close relatives
Same atlas type, nearby scientific identity, genus, or family.
Recommended companions
Compatible cards from coherent ecosystems with matching parameters.
Similar care
Cards with similar requirements, difficulty, habitat, and husbandry profile.















































