Tropical Aquarium Fish

Blue-green, slime or smear algae

Grows rapidly in blue-green, slimy sheets. Spreads rapidly over almost everything and usually indicates poor water quality. However, blue-green algae can fix nitrogen and may be seen in aquariums with extremely low nitrates. Sometimes seen in small quantities between the substrate and aquarium sides. Will smother and kill plants.This is actually cyanobacteria. It can be physically removed, but this is not a viable long term solution as the aquarium conditions are still favorable for it and it will return quickly. Treatment with 200 mg of erythromycin phosphate per 10 gallons of water will usually eliminate blue-green algae but some experts feel it may also have adverse effects on the biological filter bed. If erythromycin is used for treatment, ammonia and nitrite levels should be carefully monitored.

Brown algae

Forms in soft brown clumpy patches. In the freshwater aquarium, these are usually diatoms. Usually indicates a lack of light or an excess of silicates. Increased light levels will usually make it disappear. Easily removed by wiping the glass or siphon vacuuming the affected area.

Green water

Green unicellular algae will sometimes reproduce so rapidly that the water will turn green. This is commonly called an “algae bloom” and is usually caused by too much light like direct sunlight.An algae bloom can be removed by filtering with micron cartridges or diatom filters. UV sterilizers can prevent the bloom in the first place. Green water is very useful in the raising of daphnia and brine shrimp.

Film algae

Grows on the aquarium glass and forms a thin haze. Easily removed by wiping the glass. Considered normal with the higher light levels needed for good plant growth.

Spot algae

Grows in thin, hard, circular, bright green spots, usually on the aquarium glass but also on plants under high light conditions. Considered normal for planted tanks. Must be mechanically removed. On acrylic aquariums, use a cloth pad or a gentle scouring pad like a cosmetic “Buff-Puff” and a lot of elbow grease. On glass tanks, scraping with a razor blade is most effective.

Fuzz algae

Grows mostly on plant leaves as separate, short (2-3mm) strands. Considered normal. It might be a less “virulent” form of “beard” algae. Easily controlled with algae eaters such as black mollies, Otocinclus, Peckoltia and siamese algae eaters.

Beard algae

Grows on plant leaves and is bright green. Individual strands have a very fine texture but it grows in thick patches and looks just like a green beard. It grows up to 4 cm. It cannot be removed mechanically. This does not indicate bad water quality but grows very fast and overtakes the tank, making it a “bad” alga. Can be eliminated with Simazine (Aquarium Pharmaceuticals “Algae-Destroyer”).

Hair algae

Grows in bright green clumps in the gravel, around the base of plants like Echinodorus and around mechanical objects. It has a coarser texture than “beard algae”. Beard algae will ripple in the water current, hair algae tends to form matted clumps. Individual strands can get to 5 cm or more. This is easy to remove mechanically by twirling a toothbrush in it. Can be troublesome if left unchecked. This is a popular food supplement for fish among European aquarists.

Thread algae

Grows in long, thin strands up to 30 cm or more. Tends toward a dull green color (hard to tell because it is so thin). Usually indicates an excess of iron (> 0.15 ppm). Easily removed with a toothbrush like hair algae.

Staghorn algae

Looks like individual strands of hair algae but tends to grow in single branching strands like a deer antler and is grey-green. Seems to grow mostly on tank equipment near the surface. Difficult to remove mechanically. Soak affected equipment in a 25% solution of household bleach and water to remove it.

Brush algae

This grows in feathery black tufts 2-3 mm long and tends to collect on slower growing leaves like Anubias, some Echinodorus and other wide leaf plants. Also tends to collect on mechanical equipment. This is actually a red alga in the genus Audouinella (other names: Acrochaetium, Rhodochorton, Chantransia).It cannot easily be removed mechanically. Remove and discard the affected leaves. Equipment can be soaked in a 25% bleach solution, then scrubbed to remove the dead algae. Siamese Algae Eaters (Crossocheilus siamensis) are known to eat this algae and can keep it in check. A more drastic measure is treatment with copper.

Prophylactics for Algae

Algal spores are everywhere and will always be present in an aquarium unless drastic measures are taken. For fish only tanks, a properly set up ultraviolet sterilizer will kill algal spores in the water and prevent them from gaining a toehold.For planted tanks, this is not a good solution since the UV light will also oxidize trace elements needed by the plants and will limit the plant’s growth potential. Unfortunately, conditions that are good for growing plants are also good for growing algae. Fortunately, plants will usually out-compete algae for the available nutrients. However, if there is an imbalance of nutrients, algae will opportunistically use whatever is not used by the higher order plants. Different algae will utilize different nutrients, causing sporadic outbreaks of new algae types in apparently stable tanks when a temporary imbalance occurs.

An ounce of prevention is worth a pound of cure. To avoid introducing a new algae type to a planted tank with new plants, a simple bleach dip seems to work well. Mix 1 part bleach in 19 parts water and dip the new plant in it for 2 minutes. Immediately rinse the plant in running water, then immerse it water containing a chlorine remover to neutralize any remaining bleach. This will kill the algae and only temporarily slow down a healthy plant. Plants in poor condition may succumb to this treatment, but they probably would not have lasted anyway.

Algae Eaters

The most effective control of algae in a planted aquaria is via algae eating fish. It is especially critical in the set up of a new tank to make sure algae does not get established before the plants have had a chance to establish themselves. For this reason and to help the biological filtration get established, it is recommended that some hardy algae eaters are added right away.

Black mollies

Black sailfin mollies are excellent candidates for the break-in period of a planted tank since they are cheap and easy to find. They are usually considered expendable and are removed after a month or so. It is important to NOT FEED THEM. If they are fed, they will not be quite so eager to consume algae. When they are hungry, they are eager consumers of most algae types seen during the break-in period.

Otocinclus sp.

Otocinclus are diligent algae eaters, but are best kept in schools due to their small size. One per 10 gallons is a useful rule of thumb. Various species of otos are seen in the shops at various times; most are good algae eaters but some seem to prefer the slime coat on fish to algae. Unfortunately, there seems to be no way to distinguish the “attack otos” from normal otos.Otos seem to be very delicate fish, but this is probably due to capture and shipping abuse rather than an inherent weakness. When a fish shop gets some in, it is wise to wait a while before purchasing to account for die offs. Most people report getting a dozen and having them die over a period of a few months until just a couple are left. Those then seem to last for a long time.

“Plecostomus” sp.

Plecostomus is the generic name for a wide range of sucker-mouth fish. Only the smaller types are useful in a planted tank, since the larger varieties tend to eat the plant right along with the algae. Two common types that are useful are the “bristle-nose plecostomus” and the “clown plecostomus” or Pekoltia. Both stay under 4″ long and don’t seem to cause too much plant damage. Sometimes broad-leafed plants like Amazon swords will be scraped a little too closely by the plecos, so they bear watching.Their diet can be supplemented by blanched zucchini and bottom feeder tablets. They also appreciate a chunk of driftwood in the aquarium to satisfy their need for cellulose. See the GOOD FIRST FISH FAQ for more information on keeping suckermouth catfish.

Siamese Algae Eater

Do not confuse this fish with the Chinese Algae Eater, which is very aggressive and does not eat algae. The siamese algae eater, Crossocheilus siamensis, is a very good algae consumer and is known to eat black brush (red) algae. The only problem is that these fish are hard to find in the United States (see the RESOURCES section of the PLANT FAQ for sources and identification paper). There are several fish in this family. The most commonly seen is Epalzeorhynchos kallopterus, commonly known as the Flying Fox. The Flying Fox is the more attractive of the two. It tends to have a brownish body with a very distinct, sharp-edged black stripe with a distinct, thin gold or bronze stripe above it. These tend to be very aggressive when they are full grown and don’t eat red algae (as far as one aquarium reference is concerned).The other member is the Siamese Algae Eater. It is the same shape as the Flying Fox but tends toward a silverish body with a somewhat ragged black stripe. There may be an indistinct gold or bronze stripe above the black. These are definitely not aggressive; they are good companions for discus and small tetras.

When they are young, the differences between E. kallopterus and C. siamensis may not be very apparent, especially if you haven’t seen both types together. Unfortunately, most wholesalers don’t sell fish to stores by their scientific name and the common names that are used sometimes get pretty silly (like “siamese flying fox”). If you really can’t tell which one the store has, buy it anyway, but be prepared to sacrifice it if it turns out to be the wrong kind (unless your fish aren’t bothered by it, of course).

Farlowella

Farlowella are useful algae eaters although they are very sensitive to water conditions. They type known as the Royal Farlowella will get too large for a plant tank and may cause damage

Lobelia cardinalis, the Cardinal Flower, is a perennial that grows 2-4 feet tall and is found in wet places, streambanks, and swamps. Leaves are lanceolate to oval and toothed. The plant flowers during the summer, with vibrant red blooms cited by Roger Tory Peterson as “America’s favorite”. A white form is also known. Discovered in Canada by explorers, it was sent back to France in the mid 1620s. The name Cardinal flower was in use by 1629, likely due to the similarity of the flower’s colour to the miters of Roman Catholic Cardinals. It can be found in North America from New Brunswick, to Florida to Texas to Minnesota, though it is most concentrated in Southern Ontario, New Brunswick, Michigan, and Minnesota.

North American indigenous peoples used root tea for a number of intestinal ailments and Syphilis. Leaf teas were used by them for bronchial problems and colds, inter alia. The Meskwaki people used it as part of an inhalant against catarrh. Although related to tobacco, it was apparently not smoked, but may have been chewed. The plant contains a number of alkaloids. As a member of the Lobelias, it is considered to be potentially toxic.

Limnophila aromatica (synonym: Limnophila chinensis var. aromatica; also called rice paddy herb) is a tropical flowering plant in the plantain family, Plantaginaceae. It is native to Southeast Asia, where it flourishes in hot temperatures and grows most often in watery environments, particularly in flooded rice fields. It is used in Vietnamese cuisine and also cultivated for use as an aquarium plant. The plant was introduced to North America in the 1970s due to Vietnamese immigration following the Vietnam War.

L. aromatica was formerly classified as a member of the figwort family, Scrophulariaceae. L. aromaticoides is actually not a distinct species, but a variety of L. aromatica.

Isoetes lacustris (Lake Quillwort or Merlin’s grass) is a boreal Quillwort Lycopodiaphyte. It is native on both sides of the northern Atlantic Ocean; in Europe in Poland west to northeastern France, throughout Scandinavia, the west and north of the British Isles, the Faroe Islands and Iceland; in North America in the United States states of Maine, Vermont, New Hampshire and Massachusetts, and in Canada in New Brunswick and Nova Scotia.

The Lake Quillwort has many long, narrow leaves from 8-20 cm long and 0.5-2 mm broad, widening to 5 mm broad at the base. There is a sac that contains the spores at the bottom of each leaf base. It has a very small stem where the leaves attach with the roots. It does not have traditional roots, but instead roots with leaf-like appendages called rhizomorphs. The upper leaves are green and found in sprouting clumps.

It is found on the stony or sandy bottoms of clear, usually slightly acidic ponds, typically in mountain tarns, growing at 5-300 cm depth of water. They are perennial, with typically two flushes of new leaves each year, in spring and autumn.

Reproduction usually takes place during the late summer or early fall. The sacs at the bottom of leaf create two types of spores, female (megaspores, about 0.5 mm diameter) and male (microspores, a few micrometres in diameter). These spores begin the life cycle as a new plant.

The Common Mare’s tail, Hippuris vulgaris, is a common water plant of Eurasia and North America.

It is a creeping, perennial herb, found in shallow waters and mud flats. It roots under water, but most of its leaves are above water. The leaves occur in whorls of 6-12; those above water are 0.5 to 2.5 cm long and up to 3 mm wide, whereas those under water are thinner and limper, and longer than those above water, especially in deeper streams. The stems are solid and unbranched but often curve, and can be up to 60 cm long. In shallow water they project 20-30 cm out of the water. It grows from stout rhizomes. The flowers are inconspicuous, and not all plants produce them.

Its distribution is circumboreal; in the United States it is found mainly in the northeast but extends southwards to New Mexico and Arizona. It prefers non-acidic waters.

In herbal medicine Mare’s tail has a number of uses, chiefly to do with healing wounds, e.g. stopping internal and external bleeding, curing stomach ulcers, and soothing inflammation of the skin. It has been said to absorb methane in large quantities and so to improve the air quality in the marshes where it is often found. It can however be a troublesome weed, obstructing the flow of water in rivers and ditches.

The species is also sometimes called Horsetail, a name which is better reserved to the Horsetails of genus Equisetum. These are unrelated to the water plant, though there is some resemblance in appearance.

Eriocaulon (pipewort) is a genus of about 400 species of monocotyledonous flowering plants in the family Eriocaulaceae. The genus is widely distributed, with the centers of diversity for the group occurring in tropical regions, particularly southern Asia and the Americas. A few species extend to temperate regions, with e.g. 10 species in the United States, mostly in the southern states from California to Florida, and only two species in Canada; China has 35 species, also mostly southern. Only one species (E. aquaticum) occurs in Europe, where it is confined to the Atlantic Ocean coasts of Scotland and Ireland; this species also occurs in eastern North America and is thought to be a relatively recent natural colonist in Europe. They tend to be associated with wet soils, many growing in shallow water.

The species are mostly herbaceous perennial plants, though some are annual plants; they resemble plants in the related families Cyperaceae (sedges) and Juncaceae (rushes), and like them, have rather small, wind-pollinated flowers.

Selected species

• Eriocaulon acutibracteatum
• Eriocaulon alpestre
• Eriocaulon angustulum
• Eriocaulon aquaticum
• Eriocaulon atrum
• Eriocaulon australe
• Eriocaulon benthamii
• Eriocaulon brownianum
• Eriocaulon buergerianum
• Eriocaulon chinorossicum
• Eriocaulon cinereum
• Eriocaulon compressum
• Eriocaulon decangulare
• Eriocaulon decemflorum
• Eriocaulon echinulatum
• Eriocaulon ermeiense
• Eriocaulon exsertum
• Eriocaulon faberi
• Eriocaulon glabripetalum
• Eriocaulon henryanum
• Eriocaulon kathmanduense
• Eriocaulon koernickianum
• Eriocaulon kunmingense
• Eriocaulon leianthum
• Eriocaulon lineare
• Eriocaulon longifolium
• Eriocaulon luzulifolium
• Eriocaulon mangshanense
• Eriocaulon microcephalum
• Eriocaulon minusculum
• Eriocaulon miquelianum
• Eriocaulon nantoense
• Eriocaulon nepalense
• Eriocaulon nigrobracteatum
• Eriocaulon obclavatum
• Eriocaulon oryzetorum
• Eriocaulon parkeri
• Eriocaulon parvum
• Eriocaulon quinquangulare
• Eriocaulon ravenelii
• Eriocaulon robustius
• Eriocaulon rockianum
• Eriocaulon schochianum
• Eriocaulon sclerophyllum
• Eriocaulon setaceum
• Eriocaulon sexangulare
• Eriocaulon sollyanum
• Eriocaulon staintonii
• Eriocaulon taishanense
• Eriocaulon texense
• Eriocaulon tonkinense
• Eriocaulon trisectoides
• Eriocaulon truncatum
• Eriocaulon viride
• Eriocaulon xeranthemum
• Eriocaulon zollingerianum

Calamus or Common Sweet Flag (Acorus calamus) is a plant from the Acoraceae family. It is a tall perennial wetland monocot with scented leaves and rhizomes which have been used medicinally, for its odor, and as a psychotropic drug. It is known by a variety of names, including cinnamon sedge, flagroot, gladdon, myrtle flag, myrtle grass, myrtle sedge, sweet cane, sweet myrtle, sweet root, sweet rush, and sweet sedge. Probably indigenous to India, Acorus calamus is now found across Europe, in southern Russia, northern Asia Minor, southern Siberia, China, Japan, Burma, Sri Lanka, and northern USA.

The morphological distinction between the Acorus species is made by the number of prominent leaf veins. Acorus calamus has a single prominent midvein and then on both sides slightly raised secondary veins (with a diameter less than half the midvein) and many, fine tertiary veins. This makes it clearly distinct from Acorus americanus.

The leaves are between 0.7 and 1.7 cm wide, with average of 1 cm. The sympodial leaf of Acorus calamus is somewhat shorter than the vegetative leaves. The margin is curly-edged or undulate. The spadix, at the time of expansion, can reach a length between 4.9 and 8.9 cm (longer than A. americanus). The flowers are longer too, between 3 and 4 mm. Acorus calamus is infertile and shows an abortive ovary with a shriveled appearance.

Both triploid and tetraploid calamus contain asarone, but diploid does not contain any.

Calamus and products derived from calamus (such as its oil) were banned in 1968 as food additives and medicines by the United States Food and Drug Administration.

Calamus has been an item of trade in many cultures for thousands of years. Calamus has been used medicinally for a wide variety of ailments.

In antiquity in the Orient and Egypt, the rhizome was thought to be a powerful aphrodisiac. In Europe Acorus calamus was often added to wine, and the root is also one of the possible ingredients of absinthe. Among the northern Native Americans, it is used both medicinally and as a stimulant; in addition, the root is thought to have been used as an entheogen among the northern Native Americans. In high doses, it is hallucinogenic.

The calamus has long been a symbol of male love. The name is associated with a Greek myth: Kalamos, a son of the river-god Maeander, who loved Karpos, the son of Zephyrus and Chloris. When Karpos drowned, Kalamos was transformed into a reed, whose rustling in the wind was interpreted as a sigh of lamentation.

The plant was a favorite of Henry David Thoreau (who called it sweet flag), and also of Walt Whitman, who added a section called The Calamus Poems, celebrating the love of men, to the third edition of Leaves of Grass (1860). In the poems the calamus is used as a symbol of love, lust, and affection. It has been suggested that the symbology derives from the visual resemblance of the reed to the erect human penis.

The name Sweet Flag refers to its sweet scent (it has been used as a strewing herb) and the wavy edges of the leaves which are supposed to resemble a fluttering flag.

Aponogeton crispus
This aquarium plant is native from south-east Asia. It is a submerged plant having a round rhizome which can grow up to a 3 cm diameter. The leaves have varied dimensions between 15 and 16 cm, curly edges and they are colored in light green to ferruginous brown. This plant usually has a spherical shape. It only makes one white flower. The optimal temperature is 20-30° C. The light can be very strong but half-dark is not bad either, this fact influences the color of the leaves. The ground must be full of minerals and should be formed by sand, loam and boiled peat. When the plant stops growing, the rhizome must be replaced in a new aquarium with a temperature of 15° C. It only multiplies by seeds, which have an elliptic shape, 5-6 mm length and 2 mm diameter. The have 2 prolongations which in horizontal position get curved and stuck into the ground forming the roots. It`s better to plant the seeds in a smaller aquarium first, with a water level of maximum 30 cm.

Anubias nana
It is included in Araceae family, Anubias genus. It has been studied by Engler in 1899. It is a plant with rhizome which lives in marsh. The leaves start from the rhizome and have a lance late shape. It is colored in dark green with a shining surface. It grows very low and it needs a big quantity of light, clean water and a temperature of 25° C. This aquatic plant reproduces by the rhizome. In the same time, on the rhizome there can be up to 6-8 small plants. These will only devise when they have proper roots. The maximum length is 10 cm.

Alternanthera reineckii
In aquariums it was introduced under the name of Telanthera Osiris. The plant is spread in the tropical zone of South America. It is a small herbaceous plant, which lives in marsh having two forms: emerged (in which case the leaves stretch on the ground), submerged (in which case the leaves grow up). The leaves have a wide cross shape, lance late to elliptic, and they get thinner where the leafstalk should be, or they have a very short leafstalk. They are 4 cm length and 15 mm width. The upper part of the leave is dark green to olive green, and the lower part is light green to light carroty. This aquarium plant has a variety called Alternanthera reineckii `lilacina` which grows to a length of 6 cm and 20 mm width. The superior part of the leave is light olive green or carroty green having red spots, and the inferior zone is colored in light red to dark red. For aquariums it isn`t well adapted yet, it needs a longer period of accommodation and even then it grows very low.