Introduction
Plants have been popular in aquaria for a while, they can add greatly to the aesthetic appeal of aquaria & stop fish tanks from just looking like a “cube of water”. Some of the more extensively planted aquaria are quite beautiful in their own right & they can represent a entire ecosystems in miniature. These carefully designed & crafted planted aquariums are often referred to as aquascapes.
The growing of lushly planted aquascapes has become more accessible in recent years, due to much of the required hardware becoming cheaper and more widely available. The requirements for growing plants in aquarium conditions is also much better understood. High quality lighting, aquatic plant fertilisation (including CO2), engineered plant substrates and suitable filtration are all readily available. This equipment is also much more affordable than it was a few years ago. This all makes it possible for most aquarists to easily produce very attractive underwater gardens.
In addition to their visual appeal, the inclusion of plants in aquaria provides a number of other benefits. These include -
- Water Purification - growing plants will take up fish wastes & use them as a fertiliser (this includes ammonia & some metals)
- Improved Fish Health - most fish are less stressed in planted aquaria, the plants provide cover & fish can also benefit from eating some plants.
- Plants will add oxygen & remove CO2 from the water.
- Plants can help to control algae.
- They can stabilise the pH of the tank water.
- and prevent substrates from becoming toxic.
Starting in the 1930’s and mainly developed in the Netherlands is what is often referred to as the “Dutch Style” aquarium. These tanks focus on a lush arrangement of plants, with the plants layered from front to back, low to high, and making use of a wide range of plants of different colours and textures. They are constructed in a manner similar to the more classic garden borders. Like good garden borders they can also require significant maintenance to keep them looking at their best.
Another type of aquascape is the “biotype aquarium”. This consists of fish and plants from a single area and is used to create an aquascape that tries to represent the natural environment of the area chosen.
More recently, in the 1990’s, Takashi Amano popularised an aquascape style based upon Japanese design principals. This was a much more naturalistic style of planting that was often intended to represent a larger landscape in miniature. These designs also make greater use of rocks and logs for some hard landscape elements. It is worth noting that whilst these designs look more natural than the “Dutch Style” they also often require significant maintenance.
Many of the plants that Amano used were previously not very well known. One of the carpeting plants that he used extensively was Glossostigma elatinoides. That this is an Australian native (which at the time was relatively unknown in Australia), created interest in seeing what other native plants would also be suitable for use in aquaria. Subsequent testing of Australian natives, has revealed a rich (and expanding) set of plants that are suitable for aquatic use.
Due to the efforts of some aquarists, knowledge about suitable species (& their growing requirements) is expanding, and today there is now a wider range of native aquatic plants available than ever before. There are native aquatic plants available that cover a wide variety of different forms and growth habits. With a wide range of plants tested and available, you can now achieve beautiful aquascapes by using only Australian Native plants.
What follows is an overview of some of the many native plants that are suitable for aquarium use.
Much like how gardening books break plants into different categories (i.e. trees, shrubs, ground covers, climbers), it is useful to make some similar groupings for aquatic plants. Just like with a good garden, it is important to realise that some ongoing maintenance is required to keep your aquatic garden looking at it's best.
Foreground Plants
These are the lower growing aquatic plants (somewhat analogous to ground covers & small shrubs) & they are typically planted toward the front of a planted tank. In nature they tend to be found in shallower waters at the margins of waterbodies & as a result have higher light requirements than many of the plants that people may be used to.
Elatine gratioloides - “waterwort”
Found in all states of Australia, this pale green carpeting plant is easy to grow under strong light.
Glossostigma elatinoides - “Small Mudmat”
Widespread across much of non-tropical Australia, this plant grows well under strong light. This plant was made popular by Takashi Amano in his “Nature Aquarium World” books.
Lilaeopsis brisbanica - “Brisbane River Grasswort”
A rare plant that is currently only known from a section of the Brisbane River. As well as growing in fresh water, this plant can also handle more saline conditions. It also requires high light to maintain it’s carpeting habit.
Other plants that can be used as foreground plants include -
Hydrocotyle tripartita - “Pennywort”
Glossostigma diandrum - “Small Mud Mat”
Mimulus repens - “Maori Musk”
Background Plants
These are taller plants (analogous to trees & shrubs) and as such are used toward the rear of the tank to provide height & a backdrop for the rest of the planting. Many of these plants have less demanding light requirements and this group contains many of the easier to grow plants. Many of these plants will require regular trimming to keep them looking at their best.
Valisneria nana - "ribbon grass"
One of the long time aquarium staples, this is a widely available and easy to grow plant. This plant can vary considerably over it's range and some of the different forms are worth seeking out. Due to it's vigorous nature and the ability to spread via runners, it can come to dominate if it is not regularly thinned out.
Bacopa monniera
This round leaved plant is found in shallow waters near the coastal areas along the east coast. Some forms coming from brackish water are salt tolerant. It is also found overseas where it is known of as the herb “Brahmi”.
Limnophilla brownii - “Darwin River Ambulia”
From Northern Australia, his plant has fine feathery leaves that makes for a good foliage contrast to other plants. It grows by a runner along the substrate, with the feathery upright stems. If allowed to grow above the water, the emerse leaves loose their feathery form.
Myriophyllum spp. - “Millfoil”
There are a quite a few Myriophyllum species found around Australia and most of them are suitable for aquarium use. Like Limnophilla they have feathery submerged leaves with a different emerse form. They are generally amongst the easier to grow aquatic plants.
Pogostemon stellatus - “pogo”
Found across the far North of Australia, this is a popular and attractive background plant. Depending on the original collection location are a number of different forms available. When grown under strong light the leaves will show better colour.
Hydrilla verticillata
This widespread and easy to grow plant is found in all mainland states. It can easily be confused with the introduced weeds (Elodia canadensis and Egeria densa) and in some sites two or more of these species can be found together. It can be distinguished from the introduced weeds by the toothed margins present on the leaves. It can thus be used as a direct replacement for the above weeds in aquaria and ponds.
Some other plants that make good background plants include -
Potamogeton spp. - “Pondweed”
Rotala mexicana
Triglochin procerum - “Water Ribbons”
Hygrophilla angustifolia “Willow hygro”
Feature Plants
These are more distinctive plants that are often used to create a focal point in an aquascape. As such they tend to be used in the centre third of the tank.
Eriocaulon setaceum
Found in the northern parts of Australia, this attractive fine leaved plant can be somewhat difficult to grow. It requires high light, soft acidic water and prefers lower nutrient levels.
Blyxa aubertii
This tropical plant can appear similar to Valisneria nana, but does not form any runners & stays in a tight clump. It requires good light and a fertile substrate for it’s best growth. Whilst in the wild it is an annual, with more consistent growing conditions it will last for longer than one season.
Aponogeton vanbruggenii - “NT Lace Plant”
From the tropical areas of NT and QLD, this is a distinctive plant with ruffled leaves that show striking veination. It benefits from a fertile substrate and some forms show red colouration under strong light. To survive the dry season the plants produce an edible tuber.
Ottelia alismoides
This plant is found in NT and QLD and makes a striking feature plant for a larger aquarium. It grows best under strong light and with a rich substrate. Whilst an annual in the wild, it lasts considerably longer under good conditions.
Unusual Plants
There are a number of plants that have features that make them stand out as being a bit different from most other plants.
Ceratopteris thalictroides - “Water Sprite”
An aquatic fern that is found throughout tropical Australia. In the dry season it can grow emerse, or fully submerse in the wet. It can grow either rooted in the substrate, or floating on the surface. It can be propagated from the plantlets that appear on it's fronds. It is a hardy and vigorous plant that is widely grown and readily available.
Utricularia gibba, australis - "Bladderwort"
These are insectivorous plants that trap small aquatic creatures using bladder-like traps. These highly specialised traps are triggered when these hairs at the entrance are disturbed, causing anything near the entrance to be swept in. Any small animals caught inside are then dissolved and used by the plant as a source of nitrogen. These plants are free floating and have fine thread-like leaves and stems.
Marsillea hirsuta - “Hairy Nardoo”
This fern has “four-leaf clover” type leaves which are hairy when grown in it’s normal emerse form. However, when grown in an aquarium with medium light, it’s submerse form produces runners with single lobed leaves.
Nymphaea nouchali
This is a waterlilly where the submerse form of the leaves (pale green above, purplish below) makes for a striking feature plant. It is found across tropical Australia and likes a rich substrate and water above 25 degrees. If the water is deep enough (> 30cm) it has been known to flower underwater.
Floating plants
Better used in open topped aquaria (and in outside water features), where they can be seen from above, are floating plants. Their generally rapid growth and the capacity to reduce the light from reaching deeper in the tank, can make them useful as a way to handle excess nutrient levels and to assist in controlling algae problems.
Azolla pinnata and filliculoides
These plants are widespread aquatic ferns. Outdoors and in strong light they often take on a red colour. They are undemanding and vigorous plants.
Spirodella spp. - “Duckweed”
This common floating plant has small pale green leaves with a purplish underside. As well as ducks, many fish find this a desirable food. It can however spread quickly if the fish in the aquaria are not particularly interested in it.
Marsillea mutica - “Rainbow Nardoo”
This widespread plant has leaves that look somewhat like a floating “four-leaf clover”. It is however a fern. The leaves are about 4cm across and have an attractive two toned pattern.
Ceratophyllum demersum - “Hornwort”
This is another widespread plant which is very easy to grow. It can be anchored to the substrate, but it prefers to float just below the surface. It has long been a popular aquarium plant and is good for helping to control algae. The thick floating tangles it can create are excellent habitat for young fish and tadpoles.
Some common weeds
It is also worth keeping in mind that many weeds have started out as aquarium and pond plants. You should be particularly careful with any plants used outdoors, and ensure that measures are taken to prevent any escapes into nearby waterways. The following are some of the plants that have, in the past been used in aquaria, and are now weeds. They should not be used in your aquaria or ponds and need to be differentiated from some often similar looking native plants.
Cabomba caroliniana - "Fanwort"
Egeria densa - "Dense Waterweed, Elodea"
Myriophyllum aquaticum - "Parrots Feather"
Salvinia molesta
For the more adventurous...
The plants mentioned here are only a selection of the more readily available species available, there are many more aquatic species to be found & tried. Many of these plants may not have traditionally been considered as true aquatics, but with more advanced growing conditions (i.e. high light, CO2 & good fertilisation) they have been found to perform well in aquaria.
When you are out in the field looking at fish, it is worth looking more closely at the aquatic & marginal vegetation that is around. You may spot something that is interesting and worth a try in a suitable aquarium. Many plant species are quite variable and it is worth looking for different forms of known species. Also worth seeking out are forms that may be more amenable to aquarium use - i.e. a plant growing naturally in a shady part of a creek is likely to require less light than a nearby form found in full sun.
A recent trip to the Australian Alpine areas revealed meltwater ponds full of aquatic plant life - many of these plants are worthy of further investigation. It should be noted that the form of Glossostigma elatinoides that is commonly used, originally came from Tumut.
You do not have to travel too far to find plants that have not considered tried & tested. For example, the following little known aquatic and marginal plants are listed as being found in the Sydney area -
Brasenia schreberi
Eriocaulon scariosum - common pipewort
Glossostigma cleistanthum
Hydrocotyle verticillata - Shield Pennywort
Lilaeopsis polyantha
Limosella australis - Australian Mudwort
Marsilea costulifera (syn: M. angustifolia) - Nardoo
Pilularia novae-hollandiae - Austral Pillwort - aquatic fern
Selliera radicans - grows in salt marshes & near the coast - blue fan shaped flowers
Wolffia australiana - Tiny Duckweed - the world’s smallest flowering plant
So, for those who want to head “off the beaten path” and try something different, there are plenty of choices. Who knows, what you “discover” might become one of the new aquarium staples.
In conclusion...
The plants mentioned above are only a small sample of the possible range of natives that can be used in aquaria, and the range of possible plants is still expanding. It can be seen that there is a wide range of Australian native aquatic plants that can be used to create beautiful native aquascapes. When further combined with small native fish and invertebrates, you can end up creating ecosystems in miniature.
Article By Mark Abell with assistance from Dave Wilson (proprietor of Aquagreen - a nursery specialising in Australian Native Aquatic plants and fish)
Photos by Dave Wilson & Mark Abell
References :
Diana L Walstad, “Ecology of the Planted Aquarium”, Echinodorus Publishing
Aquascaping in Wikipedia - http://en.wikipedia.org/wiki/Aquascaping
Takashi Amano aquarium photographs - http://www.amanotakashi.net/portfolio/nature_aquarium/index.html
Nick Romanowski, 1998 , “Aquatic and Wetland Plants - a Field Guide for Non-tropical Australia”, UNSW Press
G.R. Sainty and S.W. Jacobs, "Waterplants in Australia", Sainty and Associates
Aquagreen website - http://aquagreen.com.au
ANGFA Aquatic Survey Database - http://db.angfa.org.au