Aponogeton crispus is a large and showy species that comes from a large family of popular aquarium plants. Its care needs are minimal, though the dormancy period is important to plan for. Aponogeton grow fast even in tanks with poor light, fertilizer, or carbon dioxide because they are sold as bulbs. The bulb provides additional nutrition for its first few months of life. Aponogeton crispus do well in betta tanks, community fish tanks, and planted aquascapes.
There are several aquarium plants in the genus Aponogeton, including the Madagascar lace plant (Aponogeton madagascariensis) and the Wavy Aponogeton (Aponogeton ulvaceus). Aponogeton crispus is the most common to find in pet stores as a dry bulb.
- Common Names: Ruffled Sword Plant, Crisp Aponogeton
- Scientific Name: Aponogeton crispus
- Origin: South India + Sri Lanka
- Height: 15 to 20 inches
- Light Needs: Medium
- Nutrient Needs: Medium
- Carbon Dioxide: Not Required
- Growth Rate: Fast
- Ease of Care: Very Easy
Aponogeton Crispus Light Conditions
Lighting is the most important factor for growing Aponogeton crispus. They are sold as bulbs that sprout once they’ve been submerged. The leaves need lighting strong enough to fuel photosynthesis at the bottom of the tank. Medium light levels are best but some aquarists report success with this species in low light planted tanks.
The stock light that comes with most aquarium setups is not suitable for plant growth, no matter how bright. Plants need photosynthetically active radiation (PAR) to grow well. Aquariums come with incandescent or fluorescent fixtures that output light that’s nice to look at but useless for photosynthesis. LED plant lights are an inexpensive way to improve both fish viewing and plant growth.
Aponogeton Crispus Fertilizer
Aponogeton crispus do appreciate a rich substrate but don’t need one right away. The bulb they come with is full of nutrients. The plant will rely on it if it is planted in a lean soil. In an aquarium with fish the substrate will grow richer as fish waste, leftover food, and other organic matter forms a layer of mulm inside. Plant roots will then tap into it for fertilizer.
But the bulb of an Aponogeton plant won’t last forever. If your substrate lacks plant nutrients add some fertilizer root tablets. These are slow-release fertilizers that leave nutrients right at the root level, rather than in the water column, where algae will get to it.
Iron and phosphorus are two important nutrients that should be supplemented a few times per year. If your tank has fish the Aponogeton crispus hybrid will get enough nitrogen from the ammonia, nitrite, and nitrate created through the aquarium nitrogen cycle. Otherwise, choose a fertilizer that includes nitrogen (not all of them do).
Does Aponogeton Crispus Need CO2?
Carbon dioxide is a critical nutrient for all aquarium plants. They use CO2 to build body mass and most plants grow slowly or not at all if you don’t add any to your tank. Aponogeton crispus sp. red does well even without CO2 enrichment, however. Its growth will slow down but it remains a vigorous plant even without added carbon dioxide.
I do recommend using carbon dioxide if you intend on keeping several live plants together. Medium to high light but no carbon dioxide is a recipe for an algae-filled aquarium. The plants won’t be able to create enough biomass to compete. Carbon dioxide enrichment evens the playing field so plants grow lush and algae-free.
How to Plant Aponogeton Crispus
Since an Aponogeton crispus plant comes as a dry bulb they are easy to keep stored until you are ready to grow them. The bulb needs to be submerged but don’t bury the entire thing. Place it halfway into the gravel, with the round bottom pointing downwards. The tip points up, where the leaves will sprout. A bulb that is buried may end up rotting.
Some plant retailers provide sprouted or even full grown Aponogeton crispus plants. These should be planted the same way, with the bulb halfway covered. Remove any spongy material from potted bulbs. Otherwise it will interfere with the roots as they penetrate your substrate.
Aponogeton crispus plants will grow in both sand and gravel substrates. Clay-based aquarium plant substrates like Seachem Flourite are even better since they are natural looking and bind to floating nutrients for plant roots to use. They do take a lot of work to prepare for your tank, however. Washing them may take a long time since clay substrates are full of fine dust.
Aponogeton crispus leaves are large, with wavy folds and broad coverage. They make excellent centerpiece specimens that sit in the midground or background of your tank.
They are most similar to an Amazon sword plant in how you’d aquascape with them. Except that Aponogeton are even easier to care for. Large leaves will reduce incoming light for shorter species. So arrange surrounding plants with care so nothing gets shaded by your Aponogeton crispus.
An algae eating fish is a good tank mate since the leaves may grow algae with time. Smaller algae eaters like dwarf otocinclus are gentle on plant leaves. Plecostomus are too rough and may even eat new leaves.
Aponogeton Crispus Dormant Period
Aponogeton go through a dormant phase in the wild. They are found in ponds and rivers that go through a dry season. When water levels recede the plant drops its leaves and hibernates in the mud or dry soil. Once it’s been submerged, new leaves sprout.
Dormancy is important if you want the plant to live longer than a year. The plant’s growth starts to stall at around 9-10 months of age. New leaves stop being produced and the older ones will start to rot.
At this stage, you should trim back the leaves and allow the bulb to dry in a small cup of soil kept in a cool, dry place. After 2 to 3 months of rest, the Aponogeton crispus bulb should be replanted in your tank.
Conclusion
Aponogeton crispus care is simple. So long as the bulb is not buried it will send out large, bright green leaves. It does well even in aquariums that aren’t enriched with carbon dioxide. The one complication is its dormancy phase. Once an Aponogeton crispus hybrid reaches 9 or 10 months of age, you need to dry it and let the plant go dormant or it will die.
FAQs
Aponogeton crispus and other Aponogeton species don’t need carbon dioxide. They grow faster with it, however.
An older plant will send out runners if the conditions are to its liking. Aponogeton also have flowers and seeds. But you’ll need to hand pollinate them using multiple flowering plants.
