Echinodorus Lothario Care Guide (Echinodorus 'Lothario')
Echinodorus 'Lothario' is a broad-leaved sword plant grown for its handsome rosette of oval, sword-shaped leaves that carry a soft reddish or bronze flush through their younger growth. Like all swords it is a rosette plant – a rooted plant that grows as a spreading crown of leaves from a single central base rather than as a cutting-grown stem – and at a mature size of roughly 40–45 cm it makes a natural centrepiece or background feature. Hobbyists like it because it pairs the easy, forgiving temperament of the classic sword plants with a livelier, faintly coloured leaf. Like its relatives it asks for little beyond a well-fed root zone and a little patience, because it is very much a root feeder – a plant that takes most of its food through its roots rather than from the water.
1. Species Overview
The sword plants belong to the genus Echinodorus in the family Alismataceae (the water-plantains), a group native to the Americas, where its species grow in marshes, streams and seasonally flooded ground from the southern United States down through tropical South America. 'Lothario' is a cultivated variety rather than a wild species, which is why it is written with its cultivar name in single quotes and no species epithet. It is honestly one of the more thinly documented swords in the trade: it is not listed in the major plant databases such as Tropica or Flowgrow, and the information that exists comes from a handful of European and Australian nurseries and retailers. Those sources treat it as a modern nursery cultivar – one German supplier files it under "Echinodorus new cultivars" – and describe it as a red, broad-leaved "melon-type" hybrid sword, meaning it sits in the same mould as the familiar reddish melon swords (the round-to-oval-leaved Echinodorus × barthii and osiris types) rather than the plain green Amazon sword. Its exact parentage is not published, so treat any single "origin" claim with caution: the genus itself is American, and one nursery simply lists its home as tropical South America. Submersed, it produces oval, sword-shaped leaves that are green with a reddish or bronze cast, strongest in the newest growth; grown emersed (with its leaves above the water, as nurseries usually raise it), the foliage tends to be tougher and plainer, and the plant grows fresh, softer, more colourful leaves once it settles underwater. Our store lists it simply as "Echinodorus Lothario".
2. Difficulty Level and Suitability
Every source that stocks the plant rates it easy – one German nursery calls it "unproblematic", the Australian retailers describe it as easy or beginner-friendly – and that matches the reputation of swords in general, among the most forgiving rooted plants in the hobby. Because the published information is genuinely limited, this guide leans deliberately and conservatively on the well-understood needs of medium-to-large Echinodorus – both the honest and the safe approach, since the whole genus behaves much alike. It does not need injected carbon dioxide, bright light or a special substrate to survive, and it tolerates a wide span of water chemistry. Two honest caveats apply. First, like all swords it is a slow starter that dislikes sudden change; unstable conditions can trigger melting (leaves going soft and dissolving), so steadiness matters more than chasing ideal numbers. Second, nursery plants are almost always grown emersed, so a newly planted sword commonly sheds some of its first leaves as it converts to underwater growth – this is normal, not a sign of a sick plant. Given a rich root zone, stable conditions and a little patience it suits everything from a first planted community tank to a larger aquascape, provided the tank has room for its eventual size. Only the deepest leaf colour asks for more – good light and iron – and that is a bonus rather than a requirement.
3. Water Parameters
Swords are adaptable, so treat the figures below as steady targets rather than strict limits. Published data for this particular cultivar is thin, so the ranges lean on the broad, well-documented tolerances of the Echinodorus genus and on the one or two retailers that quote specific numbers; where only a single retailer offers a figure, the table says so plainly rather than dressing it up as settled fact.
| Parameter | Target range | Notes |
|---|---|---|
| Temperature | 22–28 °C | A warm-water tropical plant. A German nursery lists 22–28 °C and an Australian retailer 20–28 °C, and the genus as a whole tolerates roughly 18–30 °C, happiest in the low-to-mid twenties. Avoid sustained extremes. |
| pH | 6.5–7.5 | Only a single retailer publishes a figure for this cultivar (6.5–7.5), which sits squarely in the comfortable slightly-acidic-to-neutral band that suits swords. It tolerates a little either side, and a steady pH matters more than the exact number. |
| GH (general hardness, the amount of calcium and magnesium in the water) | Soft to moderately hard | No primary-database value exists for 'Lothario'. One retailer quotes about 4–10 dGH, and the genus is adaptable across a much wider span, so hardness is rarely the limiting factor. Hard Australian tap water is no barrier to a plant group this tolerant. |
| KH (carbonate hardness, the water's buffering capacity) | Low to moderate | Undemanding; the same retailer lists roughly 2–8 dKH. A modest buffer is fine, and swords do well in soft to moderately buffered water. |
| Nutrients / substrate | Root feeder | Feeds mainly through its roots. Wants a nutrient-rich substrate or aquarium soil, or root tabs pushed in beside the roots and topped up every couple of months, in a deep bed of around 8–10 cm. Light water-column dosing and a little iron keep the leaves healthy. |
The single most useful habit is stability: swords mind big swings in temperature or chemistry far more than the precise readings, and a root feeder like this one always does better in a rich, deep substrate than in bare gravel.
4. Lighting Requirements
Using the PAR framework common to our guides – PAR (photosynthetically active radiation, a measure of usable light reaching the plant) of roughly 30–50 counting as low, 50–80 as medium and 80-plus as high for plants (bands that differ from the coral figures) – 'Lothario' is best treated as a low-to-medium-light plant, and here the sources genuinely disagree. One Australian retailer pitches it at "moderate to high" light, arguing that stronger lighting drives faster growth and richer colour, while the reddish melon-type swords it resembles, and the genus generally, are documented as content in low-to-medium light – the classic Amazon sword grows well at around 30–50 PAR, and a comparable red melon sword is listed as happy in low-to-medium light. The practical reading is that it grows perfectly well in low to medium light as a green-to-bronze plant, and that the reddish tones it is bought for deepen only when the light, and the feeding behind it, is stronger. Medium light is the sensible sweet spot for most tanks: enough to draw out some colour and keep the plant compact, without pushing so hard that algae settles on the large, slow-growing older leaves. If you do run bright light, raise it gradually over a week or two so the plant can acclimatise, and keep the nutrients balanced.
5. CO₂ and Fertilisation
Like all plants, 'Lothario' grows by photosynthesis – using light to turn carbon dioxide and nutrients into new tissue – so more available carbon generally means faster, denser growth. Here, though, CO₂ is not required: the retailer that quotes the plant's needs says injected carbon dioxide is not necessary but beneficial, and the reddish melon-type swords it resembles are all documented as growing without it. Add CO₂ if you already run it and it will speed along an otherwise slow-to-moderate grower; skip it happily if you do not. Feeding is where this plant genuinely cares. As a root feeder its priority is a nutrient-rich substrate or root tabs (fertiliser capsules pushed into the substrate near the roots) rather than the water column – a common approach for melon-type swords is two or three tabs at planting, topped up every couple of months and increased as the plant grows larger. A comprehensive liquid fertiliser then keeps the leaves healthy, and a little extra iron and trace element helps bring out the reddish and bronze tones. If growth is strong but the colour stays plain green, that is almost always a light or iron question rather than a fault in the plant.
6. Planting and Placement
Use 'Lothario' as a centrepiece or in the midground of a larger tank, or as a background plant in a smaller one – at a mature 40–45 cm tall and fairly broad it needs room to spread its rosette of leaves, and its big blades double as a shady refuge for smaller or timid fish. The single most important rule for any sword concerns the crown: plant it so that the crown (the central growing point from which the leaves emerge) sits just at or above the substrate surface, with only the roots buried. Bury the crown and it will almost always rot, and the whole plant collapses. As a root feeder it wants a deep, nutrient-rich bed – aquarium soil, or sand or gravel enriched with root tabs – ideally at least around 8–10 cm deep for good root development. Plants are usually sold potted and nursery-grown emersed: slide the plant out of its pot, gently tease the rockwool or wool away from the roots, and trim any long or damaged roots before planting. Should a batch instead arrive as tissue culture (sterile, laboratory-grown plantlets in gel), rinse the gel away and separate the clump into individual plantlets, each set with its crown proud of the substrate. Either way it takes a little time to convert its emersed leaves to submersed growth, so give it room and patience.
7. Growth Rate and Propagation
Growth is slow to moderate: one German nursery puts it at roughly a leaf a month, an Australian retailer calls it moderate, and both are typical of the more decorative, reddish sword cultivars, which are notably slower than the plain, fast-growing Amazon sword. That is worth knowing so you are not alarmed by a plant that takes its time to establish; expect a steady procession of new leaves from the crown rather than rapid filling-in. No propagation method specific to 'Lothario' is documented, so it is best raised the way the genus is: swords propagate not from cuttings but from adventitious daughter plants, where a mature, well-fed specimen sends up a long, arching flower stalk (an inflorescence) that produces small plantlets along its length. Let each plantlet grow several leaves and its own roots, then cut it free and plant it like the parent, crown proud of the substrate. Very large old clumps can also be lifted and divided through the crown with a clean, sharp blade, giving each piece its own roots and leaves. In an open-topped tank a happy plant may push a flower stalk above the surface and grow tougher, greener emersed leaves.
8. Common Issues and Troubleshooting
Most trouble with this plant traces back to three things: the transition from emersed growth, the crown, and root nutrition. The commonest worry is early melt – a nursery plant grown with its leaves in air often dissolves or browns off some of those original leaves in the weeks after planting while new, underwater-adapted foliage grows from the crown. This is normal: keep the crown intact, trim away fully melted leaves, hold your parameters steady, and be patient rather than binning the plant. Rot of the whole crown, by contrast, usually means it was planted too deep – lift it and replant with the growing point proud of the substrate. Sudden, widespread melting in an established plant points instead to unstable water; swords dislike big swings, so steadying the conditions is the fix. Pale, yellowing or holed leaves, especially older ones, are the classic signs of nutrient shortfall in a root feeder starved of a rich substrate – the "Swiss cheese" look usually reflects a shortage of potassium and iron, cured by adding root tabs and dosing a comprehensive fertiliser rather than by anything you do to the water. A plant that grows well but stays plain green rather than colouring up simply wants more light and iron; that is cosmetic, not ill health. Finally, because swords grow slowly and hold their large leaves a long time, algae – spot algae, or black brush algae along the leaf edges – can settle on the oldest foliage, especially under strong light with unbalanced nutrients or CO₂. Shorten the lighting period, keep the nutrients balanced, remove the worst old leaves, and a clean-up crew of Amano shrimp, otocinclus or snails will help keep the surfaces clear.
A Note on the Ranges Above
The parameters and other figures in this guide are a general guideline only. Every planted aquarium is different, and the ideal balance for Echinodorus 'Lothario' depends on your lighting, your substrate, your other plants and whether you run CO₂. For help working out tank volume and the right dose of fertiliser, plant food and treatments for your system, have a look at our Aquarium Calculators.
Disclaimer
This guide is provided for general educational purposes only. It is not a substitute for professional advice, and we cannot guarantee outcomes. Individual plants vary, and the right conditions for your system depend on your lighting, your equipment and the other livestock and plants you keep. If you are unsure about anything, please get in touch with our team before proceeding.