Live aquatic plants provide hiding places, produce oxygen and are often used as living and growing decorations for aquascaping. The plants can also serve other purposes when you are breeding fishes. The plants can often provide breeding substrates and/or protection for eggs and fry. The growth of plants can compete with algae and cyanobacteria for nutrients and especially reduce nitrates. Sometimes the plants can provide a direct or an indirect source of food for the aquarium inhabitants.

This plant article is mainly about aquatic plants for ordinary aquariums. However, it is also good to know that many terrestrial plants, including common vegetables, herbs, houseplants and fruit trees can be used in aquaponics systems. This can result in a much higher efficiency in nutrient absorption, when the roots of the plants are kept wet or moist, while the main plants are above water. I will probably write a separate article about aquaponics systems in the future, but for now, onwards with focus on common aquatic plants.

If you continuously inject CO₂ into your aquarium, in combination with strong light and constant nutrient additions, all carefully regulated, you may be able to grow healthy thriving plants quickly. However, this plant article is mainly about plants that are easy to keep and can survive in suboptimal conditions. This article will focus on plants that are so easy to care for that they are suitable not only for dedicated planted tanks by plant enthusiasts, but also stand a good chance to grow in "normal" tropical aquariums without beneficial CO₂ injection. The plants will grow slower without CO₂ injection. These plants may, or may not, need some basic additional care. Good light, some root tabs or liquid fertilizers may help. Easy plants are recommended even for low-tech aquariums and beginners, but are also often used by professional aquascapers, when ease of maintenance, low cost or less trouble is a priority.

What could be wrong if easy plants die in your aquarium?

• Maybe your nutrients or mineral levels?

  Some of them could be too high, too low, or not in a beneficial form for the plants. Nitrogen (N), phosphorus (P), potassium (K), iron (Fe), copper (Cu), manganese (Mn), molybdenum (Mo) and zinc (Zn). All of these basic elements are often put into plant fertilizers, but the dosage of each may vary and different organic compunds or ions may have different effects. Some plant fertilizers for normal aquariums skip he nitrogen and phosphorus completely, since those will usually get added automatically to the aquarium anyway with fish food and fish excrements. Especially iron deficiency or potassium deficiency can easily become the limiting factor to the healthy growth of aquarium plants, if you don't use any plant fertilizer.
  
  The nitrogen cycle is very important in aquariums. If you don't know what the nitrogen cycle is, or have trouble remembering or understanding it, then study it! There are plenty of tutorials on the internet about the nitrogen cycle in aquariums.
  
  

• Maybe your chemical water parameters?

  Some of them could be too high or too low. Especially pH, water hardness and salinity should be checked.
  
  

• Maybe your water flow, air flow or water temperature?

  Most easy aquarium plants like a temperature of about 18-26°C. Preferences regarding high or low water flow, and high or low air flow, depends on the species of plants.
  
  

• Maybe your light or timer?

  The light spectrum, the light intensity, the number of hours of light per day and the regularity and the distribution of the light periods over time are important. Red and blue light in the light spectrum is usually good for the photosynthesis of aquarium plants. A normal light period for aquariums is about 6-14 hours of light per day. If you want the light on for more than a total of 8 hours per day and have lots of plants in the aquarium it might be a good idea to add a naptime during that period, or consider adding CO₂ or make sure to have aeration, or water surface agitation, to avoid serious lack of CO₂ for the plants. If there is not enough CO₂ available, the light usually ends up benefitting algae and cyanobacteria instead of the plants.
  
  

• Maybe your substrate?

  It might be too compact, too jagged or contain harmful metals. It will also influence the growth of the plants if there is limestone, crushed corals or shells in the substrate. The effect can be positive or negative, depending on the species of the plants.
  
  

• Maybe your way of planting?

  Some species of plants should not be planted in the substrate, but can instead be fastened to decorations, or kept floating freely. Some species have bulbs or rhizome that should not be completely buried. Some species of plants grow faster if their root-threads are trimmed, while others suffer and could die from the damage, if their roots or energy storage is harmed.
  
  

• Maybe the plants arrived in emers form, not submers form?

  The emers form is an above-water growth form.
  The submers form is an underwater growth form.
  
  

• Maybe an abrupt change caused the leaves to melt?

  Melted plants can often recover if the main root or energy storage is still OK.
  
  

• Maybe some of the root-threads are rotting?

  Try to remove dead and damaged root-threads.
  
  

• Maybe the plants are in a dormant period?

  Some plants need a rest period when they do not produce leaves.
  
  

• Maybe the plants are old?

  Individual plants can get old and might die of old age, but many aquarium plants can propagate without pollination and keep making young new clones or extensions of themselves. Most of the easy plants in this article can do so. When the old and haggard "mother plant" is no longer looking healthy it might be time to remove it, but keep the younger clones and let them take over the vacant spot.
  
  

• Maybe you got a damaged shipment of plants?

  Heat, cold, pesticides, draught, long time in shipping etc. can cause damage.
  
  

• Maybe you did not remove the pots or did not clean the plants?

  Aquarium plants are often shipped in plastic pots with rockwool for protection and that is ok for a time, but eventually you probably want to replant the plants in your tank substrate instead. Lead strips that are used for weighing down plants should also be removed. Other plants are shipped in in-vitro cups with growth media. The growth media should be rinsed off and not put into your aquarium. Some plants have been sprayed with pesticides prior to shipping, make sure to rinse the plants if that is the case. Some plants may secrete protective substances when agitated, it is usually a good idea to rinse new plants in a bucket with water before adding the plants to the tank. If you notice any skin irritation on your hands, clean your hands and wear protective gloves if needed. You may also see if there are any snails, snail eggs, "pest critters" or damaged leaves, damaged root threads and so on. If you have a quarantine tank for the plants it can help to avoid problems in the main aquarium.
  
  

• Maybe you have fishes, snails, scuds etc. that eat plants?

  Either remove the culprits or try other less appetizing live plants.
  If all hardy live plants also get eaten, there are still plastic plants. ;-)
  
  

• Maybe the plants are infested with "pest critters" or disease?

  If this happens it might be possible to eradicate the "pest critters" with medication or use specific species of fish, shrimp or assassin snails to keep the population of "pest critters" under control. Sometimes disease can be easily cured if it is caused by nutrient deficiency. However, if you have already tried and failed multiple times, it might also be easier to kill the plants, disinfect everything in the aquarium, disinfect all peripheral equipment and start over. The next time, preferably start with other species of plants, or maybe try with plants from a different source.
  
  

• Maybe the aquarium is infested with cyanobacteria?

  Cyanobacteria are also known as cyano, blue-green algae or slime algae.
  Fist manually remove as much cyanobacteria as you can and do a water change.
  Then cover the aquarium and turn off all light for a few days.
  Do another water change and if there is still a problem,
  then repeat the dark treatment, or try an algicide or a bacterial cure.
  If your nitrates are zero, consider adding nitrate supplements.
  If your phosphate levels are very high, even after water changes,
  try more faster growing live pants, or try phosphate removing filter media.
  
  

• Maybe the aquarium is infested with algae?

  Try adding more algae eaters of different species to the aquarium. If it is a breeding tank you might not want algae eaters in that breeding tank. If you have algae eaters in another aquarium, you can put into practice to occasionally move some plants and decorations to that aquarium. When those plants and decorations has been eaten clean you can switch them back again to the breeding tank. This way of rotating the plants and decorations lets the cleaning crew regularly eat tasty algae meals, hopefully without eggs or fry getting eaten. Different species of algae eaters have different preferences on the types of algae they like to eat. Some of the common and very useful algae eaters in planted aquariums are Ottos, Bristlenose Plecos, Real Siamese Algae Eaters, Amano Shrimps, Sherry Shrimps, Ramhorn Snails etc.
  
  Add more faster growing live plants to outcompete the algae.
  
  Try giving your plants a nap. ;-)
  Turning off (or dimming) the lights for one or two hours a day during the normal light period will shut down the photosynthesis and allow CO₂ levels in the water to replenish, similar to what happens during a temporarily cloudy sky in nature. The restored CO₂ levels in the water will give the plants a better chance when competing with the algae, when the lights get turned back on again.
  
  Try a treatment with an algicide without copper.
  
  Hydrogen peroxide H₂O₂ in a diluted water solution can be used for dipping plants, or in small doses as a spot treatment in the aquarium. It is also possible to continiously add tiny doses of hydrogen peroxide to the aquarium water, or to continiously create it using electrolysis of water, or by adding tiny traces of ozone gas O₃ with the air in the aeration of the aquarium. Be aware that hydrogen peroxide can be harmful to humans, animals and plants. Handle with care!
  
  Glutaraldehyde C₅H₈O₂ is my favorite algicide for aquariums. Products with glutaraldehyde in aquarium shops are (misleadingly) presented as liquid CO₂ or liquid carbon. Some common products with glutaraldehyde are Easilife Easy Carbo, Happy-Life Happy Carbo and Seachem Excel. Glutaraldehyde can be used by itself, but I recommend using it in combination with products containing tiny particles of ground up zeolite, such as Easilife Liquid Filtermedia or Happy-Life Liquid Filtering Medium.
  
  Glutaraldehyde can kill and repress all the types of nuisance algae I have tried it on so far, including BBA (Black Beard Algae), although it may take some time for the algae to fade away after it dies. It is usually advisable to use the recommended daily dosage written on the product to start with, but if there is a lot of algae to kill, you can possibly increase the dosage slightly, if you have prior experience. You can also spray it, or brush it, either above or under water, on especially infested places, as a spot treatment. After a few weeks the algae should have faded away and you are experienced with using glutaraldehyde. Then you might want to dose less frequently to save money and expose yourself less to it. Although a daily dose can also benefit the growth of some of your plants, it is usually good enough to dose every now and then, to keep the algae suppressed, to keep unwanted algae from reappearing and growing back. Be aware that glutaraldehyde can be harmful to humans, animals and plants. Some plant species are much more sensitive to glutaraldehyde than others, so glutaraldehyde is not always a good choice. Handle with care!
  
  If other treatments are not enough, or too expensive, you can try a treatment using an algicide with copper. Be aware that algicides with copper can often be harmful to invertebrates, some sensitive fishes and delicate plants.
  
  

To avoid confusion about invasive species:

I have noted a warning under any species listed on this page, that I do recommend for aquariums, but could be confused with invasive species in Europe of the same genus. In the end of this article there is also a list of the invasive species of aquatic plants that you should avoid if you live in Europe. Some of the invasive species of aquatic plants were very popular among aquarists in Europe, before those species were added to the EU list of invasive species. If you live in a country outside the EU, make sure any species of plants you want to buy or trade is not banned on any similar official list of invasive species in your country. Unfortunately, the plants that are easy to keep and propagate are often also the most likely to get banned.

Easy aquatic plants that I especially recommend for:
Breeding fishes, normal aquariums and aquascaping.

• Cabomba aquatica - Green Cabomba
  Warning! Do not confuse this species with:
  * The invasive Cabomba caroliniana - Fanwort
  
  
• Ceratophyllum demersum - Hornwort
  The 'Foxtail' variant is recommended, but other variants can also be used.
  
  
• Ceratopteris --- There are several similar recommended species:
  • Ceratopteris cornuta - Broad-Leaf Water Sprite
  • Ceratopteris pteridoides - Floating Antlerfern, Water Horn Fern
  • Ceratopteris thalictroides - Water Sprite
    
    
• Echinodorus --- Several species and hybrids of Sword Plant.
  Often used by discus and freshwater angelfish for spawning.
  
  
• Lomariopsis cf. lineata - Süsswassertang, Loma Fern, Round Pellia
  Looks almost like translucent seaweed. Forms clusters. Can be spread out.
  
  
• Microsorum pteropus - Java Fern - Many variants. I'll list a few:
  
  • Microsorum pteropus - Java Fern (Normal, Common, Classic, Original)
  • Microsorum pteropus 'Green Gnome' - Small, Compact Java Fern
  • Microsorum pteropus 'Greens' - Broad, Light Green Java Fern
  • Microsorum pteropus 'Latifolius' - Broadleaf Java Fern
  • Microsorum pteropus 'Narrow' - Narrow Leaf Java Fern
  • Microsorum pteropus 'Petit' - Petit Java Fern
  • Microsorum pteropus 'Philippine' - Philippine Java Fern
  • Microsorum pteropus 'Taiwan Narrow' - Taiwan Java Fern
  • Microsorum pteropus 'Trident' - Trident Java Fern
  • Microsorum pteropus 'Trident Large' - Larger Trident Java Fern
  • Microsorum pteropus 'True Needle Leaf' - Needle Leaf Java Fern
  • Microsorum pteropus 'Undulata' - Wavy Java Fern
  • Microsorum pteropus 'Windeløv' - Windeløv Java Fern
    
    
• Najas guadalupensis - Guppy Grass, Najas Grass
  Easily breaks from force, but grows fast and offers protection for fry.
  
  
• Riccia fluitans - Crystalwort, Floating Liverwort, Riccia Moss
  Traditionally a floating plant with good protection for young fish.
  Can also be tied down on wood and rocks in aquascapes.
  
  
• Taxiphyllum barbieri - Java Moss
  Probably the most common plant for protecting fry in European aquariums.
  Grows fast. Very often misidentified as Vesicularia dubyana.
  
  
• Vesicularia dubyana - Singapore Moss - Java Moss
  A hardy and popular plant for protecting young fish.
  
  
• Vesicularia montagnei - Christmas Moss
  The shoots look a little like the branches of a miniature fir tree.
  
  

Easy aquatic plants that I especially recommended for:
Normal aquariums and aquascaping.

• Anubias barteri --- Many variants.
  
  
• Anubias gracilis --- A plant with elegant, triangular leaves.
  
  
• Bacopa caroliniana - Giant Red Bacopa, Lemon Bacopa, Water Hyssop
  
  
• Bolbitis heudelotii - African Water Fern
  
  
• Bucephalandra --- Several different species.
  
  
• Cardamine lyrata - Japanese Cress, Chinese Ivy
  
  
• Crinum calamistratum - African Onion Plant
  
  
• Crinum thaianum - Thai Onion Plant, Water Onion
  
  
• Cryptocoryne aponogetifolia --- A plant that can grow very large.
  
  
• Cryptocoryne beckettii - Beckett's Water Trumpet
  
  
• Cryptocoryne crispatula var. balansae
  
  
• Cryptocoryne undulata 'Broad Leaves'
  
  
• Cryptocoryne usteriana --- A plant that can grow very large.
  
  
• Cryptocoryne wendtii --- Several different variants.
  
  
• Egeria densa - Waterpest, Brazilian Waterweed, Dense Waterweed
  
  
• Nymphaea zenkeri - Red Tiger Lotus
  
  
• Nymphoides hydrophylla 'Taiwan'
  
  
• Helanthium bolivianum 'Quadricostatus'
  
  
• Hydrocotyle leucocephala - Brazilian Pennywort
  Warning! Do not confuse this species with:
  * The invasive Hydrocotyle ranunculoides - Floating Pennywort
  
  
• Hydrocotyle tripartita - Hydrocotyle sp.'Japan'
  Warning! Do not confuse this species with:
  * The invasive Hydrocotyle ranunculoides - Floating Pennywort
  
  
• Hygrophila difformis - Water Wisteria
  
  
• Hygrophila pinnatifida
  
  
• Hygrophila polysperma - Dwarf Hygrophila, Dwarf Hygro, Miramar Weed, Indian Swampweed, Indian Waterweed
  
  
• Limnophila sessiflora - Ambulia
  
  
• Ludwigia repens 'Rubin'
  Warning! Do not confuse this species with:
  * The invasive Ludwigia grandiflora - Water-Primrose
  * The invasive Ludwigia peploides - Floating Primrose-Willow
  
  
• Sagittaria subulata - Dwarf Sagittaria
  
  
• Vallisneria americana 'Gigantea' - Giant Val, Jungle Val
  
  
• Vallisneria nana - Narrow Leaf Eelgrass
  
  
• Vallisneria spiralis 'Tiger' - Tiger Val

Lemna minor - The common duckweed

A tiny aquatic floating plant that propagates very quickly. It can become problematic in aquariums. Be aware that it will often cling on to other plants when you move the other plants to a new tank. It will also cling on to the arms of aquarists and also on to equipment such as nets, bags, bucket and hoses. It will often grow out of control and spread to more aquariums. It may get stuck in filters and clog inlets if the waterflow is high. It may soon cover all water surfaces if the waterflow is not high. It will shadow and outcompete most other aquatic plants.

There are also many benefits with this plant, but in general the common duckweed is viewed as a nuisance among aquarists, making it infamous under the monikers "aquarium herpes", "the herpes of aquarium plants" and "the herpes of the fish tank world".

Cladophora aegagropila or Aegagropila linnaei - Moss Balls

Also known as Marimo Moss Balls, these are balls of a species of algae, not actual plants. In nature the Moss Balls are usually formed by the movement of water waves in shallow lakes. To keep their spherical shape in aquariums, the Moss Balls should get turned over and shaken every now and then, or preferably continuously, to keep their shape and stay clean. They can also be divided and the pieces can grow to become new balls after a while. It is also possible to attach the pieces to decorations, if you prefer that look instead of balls.

Be aware that some Moss Balls have been found to be infested with Dreissena polymorpha - Zebra Mussel, an invasive species that can cause problems in many countries. If you want to buy Moss Balls, make sure you source is completely free of hitchhiking Zebra Mussels and if you already have Moss Balls, check them and your aquarium for Zebra Mussels.

Links to websites with pictures and information about aquarium plants:

• Aquasabi
  
  
• Aquarium Co-Op - Live Aquarium Plants Ships plants in the USA.
  
  
• Dennerle Plants Wholesaler.
  
  
• Fish Laboratory Aquatics - Aquarium Plants
  
  
• Fishkeeping World - Aquarium Plants Archives
  
  
• Flowgrow Aquatic Plant Database - All Aquatic Plants
  
  
• Tropica Aquarium Plants Wholesaler.
  
  
• Zoopet - Växter Swedish.

Some species of aquatic plants are banned in the EU! 🖐 🛑 ❌ ❗

This is because they are on the:

List of Invasive Alien Species of Union concern

The complete EU list of invasive alien species in the link above includes a variety of different types of plants and animals. More species will probably get added to the list as time goes on. Further down below I have made a short list of only the invasive alien aquatic plants.

You can search for information about invasive species at:
CABI Invasive Species Compendium.

If you live in Sweden, I also recommend:

Havs- och vattenmyndigheten

Naturvårdsverket

Short list of aquatic plants and algae that are banned in the EU:

• Alternanthera philoxeroides - Alligator Weed
  
  
• Cabomba caroliniana - Fanwort
  
  
• Eichhornia crassipes - Water Hyacinth
  
  
• Elodea nuttallii - Nuttall's Waterweed
  
  
• Gymnocoronis spilanthoides - Senegal Tea Plant
  
  
• Hydrocotyle ranunculoides - Floating Pennywort
  
  
• Lagarosiphon major - Curly Waterweed
  
  
• Ludwigia grandiflora - Water-Primrose
  
  
• Ludwigia peploides - Floating Primrose-Willow
  
  
• Myriophyllum aquaticum - Parrot's Feather
  
  
• Myriophyllum heterophyllum - Broadleaf Watermilfoil
  
  
• Pistia stratoides - Water Lettuce
  Added to the list in 2022.
  A two year transition period starts from 2 August 2022.
  The real ban starts from 2 August 2024.
  Swedish name: Musselblomma (flytväxt)
  
  
• Rugulopteryx okamurae - Invasive Macroalgae, Invasive Seaweed
  Added to the list in 2022.
  The ban starts from 2 August 2022.
  Swedish name: Asiatisk klynnebändel (alg)
  
  
• Salvinia molesta (Salvinia adnata) - Salvinia Moss, Kariba weed