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Emerged VS Submerged plants

Updated: Jun 26, 2023


There are only two ways to grow underwater plants submerged and emerged so lets start


Difference Between Emersed and Submersed Aquarium Plants

Aquatic weeds grow in reservoirs, ditches, estuaries, and other bodies of water. They are generally classified by the way they grow: submerged (growing entirely below the water's surface),

emergent (growing out of the water),

or free-floating (float flat on the water's surface).

and Submersed plants are plants growing above the water level and below the water level. We’ve all had those times where we get a bit overzealous when ordering plants online or at a fish store especially somebody’s new to the Hobby who don’t know about every plant species, and how aquatic plants are grown. The ordered plant may look different than what we are expecting or what we have seen in pictures and may think that we got the wrong plants or ordered the wrong plants. Most Plant nurseries who cultivate and sell Aquarium plants for businesses grow the plants in emersed form as promotes fast growth, free from pests and many other benefits. In this article we will discuss all that you really want to be familiar with Emersed and submersed aquatic plants. What is Emersed and Submersed mean? Submersed plants or Immersed plants are rooted in the soil and it’s complete vegetation (including leaves, stem, flowers..) stays in the water. Due to this submersed pants grow deeper depths when compared to floating and emergent plants depending on the water conditions. Submersed plants create a good habitat for aquatic animals and small invertebrates. They can also cause a large day to night swings in dissolved oxygen and water pH. Aquarium plants in submersed formEmersed plants or Emerged plants are grown partially in water. Here the roots are planted in the soil which is completely submerged and the stem and leaves exposed to open air. The exposed portion need good humidity inorder to prevent the plant from drying out. This imitates the rainforest where the plants are exposed to high humidity and we can see aquarium plants abundantly there. Aquarium plants in Emersed formTo clear things up we can say..

  • Emersed or Emerged Above water

  • Submersed or Submerged Below water

Emersed, Submersed/Submerged – How they differ ? When you have a plant in your aquarium which is grown underwater and that’s called submersed. But most plant nurseries grow aquarium plants in emersed form where their roots are grown in the water and majority of the plant parts(stem, leaf, flowers) grow out of water. This has some big advantages like the plant does not get algae, can keep snails and other pests away, stays clean, faster growth, creates a better stronger cellular structure in the plant for shipping and it’s been done for many years in the industry. The emersed technique is an excellent way to grow plants for trade, but the question that has been raised on the forums is whether the plants grown in air melt or turn to mush after they are placed in the aquarium? No, they have a larger root system, which allows the plant to hold the leaves until it transitions into its aquatic form. This is what happens in nature when plants grow on the edge of a lake, which floods, and they become completely submersed, then as the lake dries out, they become emersed in nature. When the water level is low, they normally blossom. Transition from Submersed to Emersed What would happen if you grew a plant in aquarium that was entirely submersed? It would become soft, and transform as they grow in the water. Here’s the transformation of Ludwigia inclinata var. verticillata from Emersed to submersed form: Day 1 of planting. Day 7 of planting. Day 15 of planting. Day 25 of planting.Most stem plants grow in a variety of leaf forms. Some may be rounded when grown immersed, but when grown submerged, they become needle-like and may have vibrant colours. There are also sword plants, which will change the shape of the leaf from rounded to needle-like when grown submersed. When growing submersed, instead of a purple tone or a light green, they become a dark green or a vivid red. Do you practise cutting the roots before putting a plant in or just putting the whole plant in? Those roots are on there storing nourishment for the plant, We recommend to keep the entire plant roots because some types of plants will create a new root system as they are submersed, but in the meantime, the roots that we’re growing on the plant immersed will keep the leaves from melting. When you buy a plant that has been grown emersed and want to grow it in immersed or submersed in your aquarium, it will take some time for it to convert to its submerged state, and at that time you may observe that leaves are shrinking, stems are softening and in some, portions of the plant are dying off, notably the leaves(Happens only in few plants). When they grow from emersed to submerged, they change dramatically. Some plants will look completely bright green when grown emersed, and once they’re grown submersed, they turn really bright red colour. It’s crazy sometimes the transition of some plants is literally like day and night. Tips to submerge emersed plants Following these guidelines will help you transition from emersed to submerged plants faster:

  • Proper water condition (Temperature, pH)

  • Provide fertilizers as needed

  • Appropiate light intensity

  • Proper pruning of dead leaves

Conclusion The main conclusion is a plant that has been grown emersed and want to grow it in immersed or submersed in your aquarium is not that difficult, yet they may not grow quickly enough at times. We need to give some time for the plants for the transition. During the transition, the stem may become soft, leaves shrink, and color may turn into bright red or pink. Proper water condition, fertilizers, appropriate light intensity and proper pruning of dead leaves encourage the plant growth steadily. Your aquarium plants will grow quicker than ever before if you follow the ideas and tactics we’ve discussed above



Submerged plants -There is a plethora of submerged aquatic plant species.

Some may be more prevalent in certain areas than others. Submerged aquatic vegetation are plants that are completely under the water and typically have a root system in the bottom sediment. They require the water for physical support of the plant structure.

The difference between desirable submerged aquatic plants and undesirable varieties is personal taste (how the plants look) and balance. A beautiful plant that takes over the entire pond can quickly turn from one that is pleasant to one that needs to be killed off. Keeping plant species in check and in balance will create a beautiful pond setting. Below are some common submerged aquatic plants and some information about them.

Muskgrass (Chara spp.) is actually a form of erect algae. It is a great plant for ponds with excessive nutrients because it uses up a large amount of nutrients and provides food and hiding for fish and other organisms. It can look like several other aquatic plants, but a way to tell it apart is to break the thin straw-like stem. Since it is a single celled stem, if you break it, the entire stem will turn flaccid. Other plants will just break or bend, not turn flaccid. Also has a strong garlic smell to it. As with many plants, it is good in moderation. The pond above is a bit over grown.


Pondweed (Potamogeton) is a thin leafed aquatic plant that is native to many areas. This plant can serve as a food source and hiding place for organisms in your pond and produce oxygen. Since it is native, it is not as invasive as non native plants, but it must be kept in moderation. This picture is of young pondweed before it puts out is surface leaves. Some consider pondweed as a floating plant due to these surface leaves.

Eurasian Watermilfoil (Myriophyllum spicatum) is not native to the US and is an extremely invasive species. There are strict regulations for boats in lakes that contain eurasian watermilfoil because small pieces that break off can stick to boats and trailers and then re-root in other bodies of water. The leaves are feather-like and are limp when out of water. The leaves are arranged in circles of 3 to 5 around a long, spaghetti stem. The plants can grow over 10′ tall. The tops of the stems often are reddish in color.


Bladderwort (Utricularia purpurea) is an aquatic plant that can live in ponds with limited nutrients available. It is actually a carnivorous plant. It can look like an unorganized mess in your pond, but it eventually comes together to form the “starfish” shape and then shoots up the yellow flowers. Black bladders hang below that open and catch small organisms like zooplankton. Bladderwort can be a pain if it takes over your pond and since it isn’t as dependent on nutrients in the pond, it can spread rapidly.

Hydrilla (Hydrilla verticillata) is an undesirable aquatic plant with long, branching stems. Hydrilla often fragments and form large floating mats. It produces tiny white flowers in early fall. It can be differentiated from Elodea or Egeria with its sharp toothed leaf margins. Hydrilla feels brittle to the touch. Hydrilla can grow in shallow or deep water and can quickly spread throughout a body of water. – photo courtesy of The Lake Doctors, Inc.


Common Waterweed (Egeria densa) is branched and has a long, narrow stem with dense leaves found in whorls of 4. The leaves can be oblong or linear and are very fine toothed. It produces flowers that are white with yellow anthers. As with many aquatic weeds, it needs to be controlled to prevent overtaking your pond. – photo courtesy of The Lake Doctors, Inc.


Elodea (Elodea canadensis) is commonly confused for hydrilla or egeria, but is much smaller in size. The leaves are bright green, in whorls of 3, and elliptic to oblong. Small white flowers are produced from mid summer to fall. Needs to be kept in check to limit spreading. – photo courtesy of The Lake Doctors, Inc.

Coontail (Ceratophyllum demersum) is a submersed aquatic plant, but does not have any root structure. The feathery, fan shaped leaves are arranged in whorls with small teeth and resembles a raccoon tail. Coontail can grow very tall (15′) and occur in deep water areas. Controlling the spread of coontail can be difficult since it is free floating. – photo courtesy of The Lake Doctors, Inc.

The emergent and submerged growth of aquatic plants

Aquatic plants are commonly available in most aquarium stores and can generally be divided into two types: Emergent and submerged. These two terms are defined by how we grow these plants within the aquarium.

In nature, the plants that we view as aquatic plants most likely do not live 100% beneath the water surface. While some plants do, it is much more common to find our favourite aquatic plants growing on land along the shoreline and shallow areas of lakes, rivers, streams and shallow ponds while also being exposed to natural sunlight, collecting nutrients via their root systems and substrate. Many of these locations will receive seasonal flooding, forcing the plants into a fully aquatic setting for short periods. However, the majority of the year will see only their roots set underwater.

This is very common in low flood plains, where plants will survive several months below the water's surface. While there are undoubtedly benefits to being underwater, this setting exposes plants to the many pollutants in natural waterways. We must acknowledge that things are different in nature compared to the closed environment of an aquarium. It is not practical for us to change the water level all the time, so we must choose our plant species according to the layout and style of the aquarium we are planning.

The main difference between these two categories can easily be explained. Emergent plants grow above the surface of the water, while submerged plants grow within the water column below the water surface. There is usually a difference in sale price too. It is a costly process to create conditions suitable for growing submerged plants. Growing aquarium plants emerged is more cost-effective and quicker!

First of all, let us clear up a common misconception.

"Plants grown above water do not adapt to the aquarium as good as plants that are grown underwater."

Usually, when an aquatic plant from an emergent cultivation is placed underwater. Unlike submerged vegetation, emergent aquatic plants original leaves (produced in terrestrial conditions) will melt. Without understanding this stage of the plant's adaptation to the new environment, many aquarists quickly assume the erosion of leaves indicates their new plants have failed.

However, it is worth waiting for this situation to play out. Patience is an aquascapers secret weapon.

This process takes time, and we should always expect some leaves to melt away. New leaves will appear as long as we provide food and the aquatic plants are well rooted in the soil. The newly released underwater leaves often contrast with the original leaves with slightly different shapes and colours. Strangely, when plants more used to growing on dry land above the water surface become submerged, form new leaves that are more rounded than before. The fresh leaves are entirely normal and all part of the process of adapting.

Depending on the type of aquatic plants - adaptation takes various forms.

  • Plants with long stems (Stem plants such as Rotala, Ludwigia, Limnophila, Myriophyllum) adapt to underwater conditions.

  • Plants of the genus Hygrophila, Alternanthera adapt longer than the above. It will lose leaves close to the substrate when in a low light penetration habitat.

  • In most cases, plants of the genus Cryptocoryne (which applies to both emergent and submerged plants) will lose their leaves (Also known as 'Cryptocoryne Disease'). It would help if you cut the diseased leaves, leaving only the rhizome behind - in the next few days, new plant growth will begin to form, fully adapted to the conditions in the aquarium.

  • Plants of the genus Echinodorus can quickly adapt to the aquarium habitat depending on the species (colourful artificial hybrid strains adapt more difficult). Most often, the adaption process begins with a mesh on the surface of the leaves and, ultimately, the death of the entire leaf blade. In the next few days, new plant growth appears from the rosette, adapted to the conditions in the aquarium.

  • Plants of the genus Microsorum, Anubias - adapt to the aquarium without any problems. This is because their native habitat is the banks of rivers, streams and wetlands.

The information above is relevant to aquariums suitable for each plant species. Adequate lighting power (minimum 0.4W / l for smaller aquariums), soft-medium hard water and pH 6.5-8, fertile soil and carbon dioxide. When adding new emergent plants to the aquarium, the provision of CO2 will also significantly increase your plant's recovery time. We must consider that all plants initially grown in emergent conditions have had access to unlimited atmospheric Carbon Dioxide. It only makes sense to provide them with additional CO2 to compensate for this new habitat.

Emersed plants available in local fish stores are more durable than plants grown in underwater.

  • They grow under natural light, which promotes a fast metabolism, and appropriate levels of enzymes and plant hormones, not limited by the availability of nutrients in the water. This environment builds vigorous, resilient plants capable of being successfully introduced to the aquarium environment.

  • Plants growing above the water surface have stronger stems, which are very beneficial when transporting plants from the supplier to the shop and from the shop to your aquarium.

  • They have a considerable amount of stored nutrients, which comes in handy while adapting to their new underwater habitat.

  • They are free from waterborne diseases and parasites. No more pest snails hitchhiking their way into your aquarium.

  • Free of hard-to-remove algae spores and cyanobacteria. Ultimately algae-free plants, leaving the algae battle ball in your court. You should see no unwanted algae in the aquarium if you provide the correct care.

The most common mistakes and problems with plant adaptation which are contributing to the myth that plants cannot adapt successfully to the aquarium habitat:

  • Impatience: Removing plants when their old leaves die off. Always allow time for the new aquatic leaves to form.

  • Lack of nutrients: Placing new aquarium plants in sterile substrates like plain gravel will not be sufficient enough to sustain the new growth during the transitional period.

  • Poor Filtration: Inadequate filtration can cause a build-up of unwanted materials and invites algae to form.

  • Inadequate lighting: Plants need light. Strong, consistent lighting periods are essential to photosynthesis, which is vital to all plants' growth. Research your plant's requirements and use a timer to provide the relevant length and strength of light (photoperiod)

  • Lack of CO2: Plants require carbon dioxide. While the fish generate a small amount in your aquarium, this will not be sufficient for most aquarium plants. The provision of co2 will significantly benefit the plants during their transitional period.

  • Irregular water changes: A lack of regular water changes harms aquariums, but when adding new plants, it is essential to do weekly water changes to maintain the optimum conditions.

  • Incorrect water parameters: Just like fish, they require specific conditions. Ph, temperature and hardness are all elements we should aim for to give transitional plants all the tools they need to thrive.

Summary

Maintaining an aquarium with both submerged and emergent growth is possible. The modern aquascaper can benefit from access to high-quality substrates, nutrients, lights, and CO2 injection. So, with a bit of forward-thinking, you can enjoy a beautiful display with all different types of plants.

Some species even produce flowers once established, which can be highly satisfying. Why not try creating a shallow pond-style aquascape that combines both submerged and emerged growth. This design pulls together both categories to create a very natural displa

Emerged plants - plants are grow above water in soil but in closed container






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