Blub

Rainbow Shark
(Epalzeorhynchos frenatum)

Common names: Red-fin shark, Red-finned shark, Rainbow shark, Albino red-fin shark, Albino rainbow shark
Size: 15cm
pH: 6.0 – 8.0
Tempº: 24ºC - 27ºC
Tank region: Bottom layer
Origin: Thailand, Indonesia, Cambodia.
Gender: The male’s anal fin is distinctively black-lined.
Notes: Not to be kept with other freshwater sharks – or even other red fins. These fish can be aggressive; and will most likely stake out a ‘territory’. If you provide them with lots of caves though, they should become less aggressive. Needless to say, the Rainbow shark can be a good community fish, as long as it is housed with the right species and are a slightly more peaceful alternative to the closely related Red-finned black shark. As they age, they become more aggressive. There is a popular albino form of this species available.
Left Image: A Male Rainbow Shark.
Center Image: The Albino Rainbow Shark is just the same in terms of care as the standard Rainbow shark, but has a totally different aesthetic! Photo credit goes to Jglove276 - thanks for letting me use this!
Right Image: This species spends most of it's time on the substrate. Photo credit goes to Jglove276.

Blub

Common names: Red-tailed black shark, Redtail shark
Size: 10-15cm
pH: 6.0 – 8.0
Tempº: 24ºC - 27ºC
Tank region: Bottom layer
Origin: Thailand
Gender: Females are larger, females have a grey stomach – males are black.
Notes: This semi-aggressive fish is solitary by nature and appreciates lots of hideouts. Because of it’s territorial nature, it is not the best choice for community tanks as it can harm smaller, or weaker fish. As they age they become more aggressive. They are however hardy fish that does well with robust fish that aren’t too small, such as the Tiger barb. It is a herbivorous species, but not a particularly effective algae eater.
Left Image: A swimming Shark
Right Image: A Red-Tailed Black Shark investigating a plant

Blub

Common Hatchetfish
(Gasteropelecus sternicla)

Common names: Common hatchetfish, River hatchetfish, Black-lined hatchetfish, Silver hatchetfish
Size: 4cm
pH: 6.0 – 7.5
Tempº: 23ºC - 27ºC
Tank region: Top layer
Origin: Brazil, Peru, Guyana, Venezuela
Gender: Females are larger.
Notes: These fish are somewhat rarer than their marbled cousin but deserve theit place in the aquarium just the same. However, they are not as pretty, as they do not have the patterning of the Marbled hatchetfish. They are very peaceful and confine themselves to the top layer – with a few trips to other layers. They can jump up to 2m I nthe air – so a tight cover is an essential for a hatchetfish tank. They appreciate floating plants. Common hatchetrfish are relatively hardy.

Although they are not the prettiest fish at first – they look amazing when they are under a good light. They also make up for their somewhat dull appearance with a funny personality – and a quirky shape!
Image: Common Hatchets are fantastic aquarium fish. Image credit - Blub. My own photo.

Blub

Otocinclus Catfish
(Otocinclus vittatus)

Common names: Otocinclus catfish, Oto, LDA23, Dwarf suckermouth cafish, Dwarf sucker.
Size: 3.5-5cm
pH: 5.5 – 7.5
Tempº: 21ºC - 26ºC
Tank region: Bottom layer
Origin: Brazil.
Gender: Difficult to determine, although adult Females are larger.
Notes: This charming little fish is a fantastic community fish. There are about a dozen very similar species of Otocinclus available in the aquarium trade – but to be honest it doesn’t really matter if you have O.vittatus, O.mariae, O.macrospilus, O.vestitus or any of the other Oto species as they are almost identical in both aesthetics and care! However, since this profile is about O.vittatus, the information on origin and LDA number is different for other Oto species, but the general care is the same. Otos are schooling fish which really appreciate the company of a large group, which is not a problem as they are very small, thus they have a low bioload and they eat lots of algae. They are the perfect addition to a planed tank as they will gobble down algae on plant leaves and on the tank walls. This species is an ideal tankmate for small tetras, rasboras, peaceful barbs, danios, corys, shrimp and livebearers and won’t bother other fish in the community. However, care should be taken not to house them with fish that might eat them! This fish is often starved at the fish store, as they are often said to just eat algae when in reality it is a good idea to give them other foods as well, such as vegetables or bottom feeder pellets because, quite frankly, they will quickly eat the algae and have no food left. Because they are often starved at the store, they often arrive home very hungry and weakened. It is therefore a good idea to keep them in a small quarantine tank and fed on fish flake, bottom feeder pellets/wafers and frozen bloodworms (sparingly) for a few weeks before they are introduced to their final home. This is the ensure that they are strong and healthy before being unleashed onto the chaos of community life. A word of warning on the filter: make sure that an unsuspecting oto can’t be sucked into it as this has been the end of many an oto.
Left Image: O.mariae - an almost identical species to O.vittatus in both looks and care.
Right Image: O.macrospilus - another species that is pretty much a clone of O.vittatus in aesthetics and maintenance.

Blub

Common names: Zebra otocinclus catfish, Zebra oto.
Size: 3.5-4.5cm
pH: 6.0 – 7.5
Tempº: 21ºC - 25ºC
Tank region: Bottom layer
Origin: Peru.
Gender: Difficult to determine, although adult Females are larger.
Notes: The Zebra Oto has only been part of the aquarium trade since the new millennia, but it has already made quite an impact with it’s fantastic looks. Even better, it is just as peaceful and fun to watch as any other Otocinclus species, not to mention it’s trademark Otocinclus algae eating quality’s. As with other otos, the Zebra oto is a schooling species so be sure to keep it in groups of at least 3 – although 6 is better. They enjoy a planted tank, where their algae eating qualities will be greatly appreciated!
Image: Zebra Otos are truly fantastic looking fish!

Blub

Common names: Peppered otocinclus catfish, Peppered oto.
Size: 5.5-6cm
pH: 5.0 – 8.5
Tempº: 20ºC - 27ºC
Tank region: Bottom layer
Origin: Brazil.
Gender: Difficult to determine, although adult Females are larger.
Notes: This unusual Oto is a bit larger than your average Oto but just as friendly. In the wild, they imitate the similarly patterned Peppered cory (Corydoras paleatus), swimming around with them, going to gulp for air when they do, and in turn the corys behave in a similar way – even trying to breed with Peppered otos on occasions! The otos do this because of their lack of natural defense – and the peppered cory has poisonous spines! This evidently helps protect the Peppered oto from predators – as in a mixed school of Peppered otos and corys predators are going to have a hard time picking out a fish that isn’t poisonous! It is unclear what the corys get out of this, but obviously there are more eyes and more bodys to hide amongst if predators do show up. In the aquarium, Peppered otos and Peppered corys will scool together, and whilst Peppered otos can be kept without their cory counterparts it is a far more outgoing and active species when the corys are around. Indeed they can become fairly shy if not kept with the corys. For this reason it is recommended that you have at least 5 peppered otos and 5 peppered corys in the tank. They are less reliant on plants than other species of Otocinclus, but plants are a good addition to their tank even so. They should eat vegetables (cucumber goes down well) and bottom feeder pellets/wafers.

Blub

Common names: Emperor tetra, Rainbow tetra.
Size: 5cm
pH: 5.0 – 7.5
Tempº: 23ºC - 27ºC
Tank region: Middle layer
Origin: Columbia
Gender: Males are larger and develop extended anal, dorsal and caudal fins as they grow. Males iris’s are blue, female’s are green.
Notes: This stunning tetra is a fantastic schooling fish for the aquarium. They are peaceful, and need to be kept in groups of 6. They will take pretty much any food offered! You may often find Inpaichthys kerri offered for sale as N.palmeri – but they are not as colorful, does not develop trailing fins and doesn’t have colored eyes! Fortunately, it easy to tell them apart when young though, as N.palmeri lacks an adipose fin, but I.kerri has an adipose fin!

Blub

Purple Emperor Tetra
(Inpaichthys kerri)

Common names: Purple emperor tetra, Blue emperor tetra, emperor tetra.
Size: 3-4cm
pH: 5.0 – 7.5
Tempº: 24ºC - 28ºC
Tank region: Middle layer
Origin: Brazil
Gender: Males have larger fins, and the male’s andipose fin is blue whilst the female’s is red.
Notes: This small tetra is often sold as Nematobrycon palmeri, but it is easy to tell the difference as this fish has an adipose fin, and N.palmeri lacks the adipose fin. They are simple to care for , but can be rather delicate. They need to be kept in a school of at least 6.

Blub

Common names: Congo Tetra.
Size: Males 8-10cm (although 8cm is more common), Females 6-8cm (although it is unusual for them to reach 8cm).
pH: 6.0-7.5
Tempº: 23ºC - 27ºC
Tank region: Middle layer
Origin: Zaire.
Gender: Males are larger, with more colour, with a more extended tail and dorsal fin. A mature males tail will have an extension, a mature female’s tail will be more rounded.
Notes: Possibly the most common African Tetra offered for sale, the Congo tetra is quite a stunning animal to behold. They can be fairly timid; although they become bolder with time. Because this fish is quite large (especially for a tetra!), it is a good idea to provide it with plenty of swimming space in a tank of about 90-100cm long. As they are a tetra, they need to be kept in schools of at least 5-6 to keep them happy. They tend to be a bit expensive, but are quite hardy so you don’t have to worry about losing them if they’re kept in good conditions. Overall a beautiful African tetra for the planted tank or Biotype.
Image: A male congo tetra. Note the Tail extension.

Blub

Common names: Blind Cave Tetra, Mexican Tetra, Blind Cave fish, Blind Tetra, Slivery Tetra.
Size: 7-9cm.
pH: 6.0-8.0
Tempº: 20ºC - 25ºC
Tank region: All Layers.
Origin: Texas, USA, Mexico.
Gender: The anal fin of the male is slightly curved, the female’s is straight. As with many fish, the female tends to be more fuller bodied than the male.
Notes: The blind cave tetra is both a very strange creature and an evolutionary marvel – it is completely blind but seems to be able to navigate around it’s habitat like any other fish. The reason for this – (as the name suggests) is that it lives in underground caves. In the caves in which it lives – there is almost no light making eyesight almost useless, so it has no eyes! It also has lost all it’s pigment, making it look a bit like an albino. When a baby emerges from it’s egg, it actually has eyes but these soon degenerate if kept in complete darkness. There is also a surface dwelling variant of this species – which has eyes and pigment but is not overly popular in the aquarium trade – unlike it’s unusual sibling. It is thought that the two forms split up only 10,000 years ago – which makes the Blind cave tetra even more fascinating as it has gone through a significant evolutionary change in a relatively short space of time. There is also a completely separate species of Blind cave tetra – Astyanax jordani which is thought to have evolved separately from the Blind form of A.mexicanus. You may be wondering how it on earth it finds it’s way around; the answer is simple: it uses the lateral line system found to detect small changes in water pressure, allowing it to avoid obstacles and find food. When introduced into a new tank, they are often observed swimming faster than normal – possibly building up a ‘picture’ of their environment in their mind. Even more interesting – as they are bred in huge numbers in the far East they seem to be developing their silvery sheen on their flanks – effectively, the evolutionary process is reversing!

In terms of care – the Blind cave tetra is fairly easy. It will take commercially prepared food, and make good beginner’s fish as they are quite hardy. It is important to keep it in a school of at least 5-6. Décor is not important – but can be added. You could have fun though and create a rocky ‘cave’ habitat for a single species set-up! They are fairly peaceful and make good community fish.
Left Image: A Blind Cave Tetra
Right Image: The surface form of A.mexicanus with the Blind cave form. The Surface form is the bottom fish.

Blub

Common names: Silvertip tetra, Silver Tipped tetra, Silver tip tetra.
Size: 5cm.
pH: 6.0-8.0
Tempº: 22ºC - 28ºC
Tank region: Middle Layer.
Origin: Brazil.
Gender: Males have a tend to be more vibrantly colored and slimmer.
Notes: As with most small tetras, the Silvertip tetra is an active, social little creature. They generally prefer a planted aquarium, and should be kept in groups of at least 5-6. They are quite hardy, making them suitable for the beginner.
Image: Silver Tip Tetras are Peaceful community fish.

Blub

Common names: Buenos Aires Tetra, Diamond spot Tetra.
Size: 7.5-10cm.
pH: 6.0-8.0
Tempº: 18ºC - 28ºC
Tank region: Middle Layer.
Origin: Brazil, Paraguay, Argentina.
Gender: Males are more brightly colored and slimmer than females.
Notes: The Buenos Aires Tetra is one of the larger tetra species; but it’s care is much the same as its smaller cousins. It is a peaceful species which enjoys the company of it’s own kind and should be kept in groups of at least 5-6. There are two varieties available – the ‘regular’ Buenos Aires and the Albino Buenos Aires. Unlike most tetras, it will eat live plants so it is a bad idea to put a school in your planted tank! Because of this, it is advised to furnish their aquarium with rocks and wood. It is very hardy – so makes a good choice for beginners seeking some larger schooling fish.

Blub

Common names: Dwarf pencilfish.
Size: 3.5-5cm
pH: 5.5-7.0
Tempº: 24ºC - 28ºC
Tank region: Middle -Top layer
Origin: Suriname, Brazil, Peru, Guyana, Columbia.
Gender: Adult males show more red on their fins than females, and are slimmer.
Notes: This small pencilfish needs to be kept in schools of 6 or more. They are fairly timid, and should not be kept with overly boisterous tankmates or fish much bigger than them so they don’t get outcompeted for food. A low light planted tank is ideal for this species, as they love plants in and do best in shady conditions. It is a good idea to include floating plants in their tank, as this creates an ideal shady retreat. Feeding these fish should be easy, as they should take most small foods.

Blub

Common names: Three-Lined Pencilfish, Three-Banded Pencilfish,
Size: 5.5-6cm
pH: 5.5-7.0
Tempº: 24ºC - 28ºC
Tank region: Middle -Top layer
Origin: Guyana, Brazil, Peru, Bolivia, Columbia.
Gender: Difficult to tell, but males tend to be more brightly colored and slimmer than females.
Notes: Like most Pencilfish, the Three-Lined Pencilfish is a relaxed and peaceful species hailing from South America. It is an ideal tankmate for other small characins, small catfish, gouramis and other peaceful community species. It is best not to keep it with fishes much bigger than itself; as it can easily be outcompeted for food due to it’s rather shy nature. Being a schooling fish, it is essential to keep them in groups of at least 6 or more to ensure the fish’s happiness. Feeding these fish is easy, as they should take both small commercially available foods and live foods.
Image:A trio of Three-Lined Pencilfish.

Blub

Nerite Snail
(Neritina natalensis)

Common names: Nerite Snail, Nerite, Zebra Nerite, Tracked Nerite.
Size: 3-5cm
pH: Not below 7.0.
Tempº: 22ºC - 26ºC
Tank region: Bottom layer
Origin: Kenya, Mozambique, South Africa, Tanzania, Somalia.
Gender: N/A
Notes: The Nerite Snail is a very popular Aquarium species because of it’s attractive shell, small size and hearty appetite for algae. Several subspecies are available, with different colours – the most popular are ‘sp. “Zebra” and ‘sp. “Tracked”. They are generally hardy, and are incredibly peaceful. For this reason they are an excellent addition to community tanks. They are also popular in Planted Tanks because of their excellent algae eating capabilities. It is one of the only species compatible with a male betta, who will often ignore them.

This Snail’s eggs only hatch in brackish water, but it will lay lots of eggs on filters, bogwood and rocks in freshwater.
The snail can be kept successfully in both Brackish water and Freshwater.
It should not be housed with Loaches or other snail eating species. The Nerite Snail can sometimes find itself upturned on the substrate – if you see your snail upside down, flip it over as soon as possible. If left upside down for too long, they can die. Another thing to watch for is escaping snails. They can survive out of water for some time, and can often climb out of tanks without a secure hood. If you do not have a hood and the snail is missing, then thoroughly check the area around the tank!
Image:A Zebra Nerite Snail.

Blub

Common names: Glass Catfish, Glassfish, Ghost Catfish, Asian Glass Catfish, Phantom Catfish.
Size: 8cm
pH: 5.5 – 7.5
Tempº: 21ºC - 26ºC
Tank region: Middle Top layer
Origin: Thailand, Malaysia, Indonesia.
Gender: Unknown.
Notes: The Glass Catfish is a true Oddball in the Aquarium. Not only does it have a very unusual body shape, and it is one of the only top dwelling Catfishes but it’s body is entirely transparent! This allows it to ‘disappear’ in the wild, where it often lives in murky water. This fish should be provided with clean, preferably slightly acidic water in the Aquarium however, where it makes a fantastic and peaceful addition to a larger community tank. Glass Catfish should always be kept in schools of 6 or more because of its gregarious nature, and it will do best in a well planted tank. However, it is important to provide free swimming space as well because the Glass Catfish can be quite active.
This fish can be kept in slow moving water or in a slight current, but is not suitable for a mountain stream type environment. The species is incredibly peaceful, and thus makes an excellent addition to a placid community. Reccomended tankmates include small Rasboras, Tetras, Corydoras and peaceful Barbs.

It should be noted that this fish is often confused for a very similar species – Kryptopterus bichirris. However, K.bichirris is in fact very rare in the Aquarium Trade, and will grow to almost twice the size of K.minor. It is likely that K.bichirris has been imported in the past, but is much rarer than K.minor.
It is possible that the first specimens of K.minor where actually imported before K.minor was scientifically recognized – it was only described in 1989 so it would make sense that imports before then where labeled K.bichirris.

Whilst most of the Glass Catfish’s body is transparent, only the skeleton and Swim Bladder are clearly visible. The rest of the fish’s organs are packed into the front half.
Image: The Glass Catfish sports an unusual body shape and is mostly transparent!

Blub

Common names: Gold Tetra, Golden Tetra.
Size: 5cm
pH: 6.0 – 7.0
Tempº: 24ºC - 28ºC
Tank region: Middle layer
Origin: Guyana.
Gender: The anal fin of the female has a red hue, and a white leading edge.
Notes: This small Amazonian species is an excellent fish for a community aquarium thanks to it’s small size and peaceful nature. As with all tetras, the Gold Tetra needs to be kept in schools of at least 6 or more to avoid stress. Gold Tetras are slightly delicate, so should be added to an established tank with stable water parameters. They enjoy the cover provided by a planted tank, and will readily accept processed Flake Foods. Gold tetras are very beautiful in the aquarium, and can be quite energetic so open swimming space is a must as well as some cover.

Blub

Common names: Hoplo, Spotted Hoplo, Hoplo Catfish, Port Hoplo, Armoured Catfish, Armoured Hoplo, Black Marble Hoplo, Hoplo Cat.
Size: 12-15cm
pH: 6.0 – 8.0
Tempº: 18ºC - 28ºC
Tank region: Bottom layer
Origin: Widespread across Northern South America.
Gender: The first ray of the male’s Pectoral fin is slightly orange, and thicker than that of the female. When in breeding condition, males will have a more colourful belly.
Notes: The Hoplo Catfish is closely related to the popular Corydoras genus, and in many ways can be regarded as a much larger Cory in the aquarium. These fish are a boisterous and gregarious species, which should be kept in small groups. Hoplos are best kept in a large tank with a sandy substrate, and whilst they come from very still waters in the wild they can adapt to a faster current in the Aquarium. Hoplo Catfish are very peaceful, making them a good choice for a large community tank. All in all, this is a very adaptable and hardy bottom dweller for larger tanks.
Image: The Hoplo Catfish is by no means colourful, but is a very attractive fish nevertheless.

Blub

Common names: Yoyo loach, Almorha Loach, Pakistani Loach, Reticulated Loach, Pakistan Loach.
Size: 10-15cm
pH: 6.5 – 7.5
Tempº: 18ºC - 28ºC
Tank region: Bottom layer
Origin: India, Nepal, Bangladesh, Pakistan.
Gender: Females are more full bodied than males.
Notes: The Yoyo Loach’s popular common name comes from the unusual marking on it’s side. If you look closely, you will see the word ‘YoYo’ written on the fish’s side! This name is also a testament to the Yoyo Loach’s playful and boisterous nature. As with all Loaches, the Yoyo loach is gregarious and should be kept in groups. It requires a large aquarium because of it’s potential size, and plenty of caves to hide in. As a general rule, the more caves you have the more confident and active the fish will be. They are quite peaceful, and are suitable for most community aquariums. However, small shy fish may be intimidated by it’s size. Ideal tankmates include Danios, Rasboras and peaceful Barbs.
Yoyo loaches are omnivorous, and will readily accept processed food. These fish have no scales, and enjoy a soft sand substrate to dig in.
Image: If you look closely, you will see the 'YoYo' pattern that gave rise the this species common name.

Blub

Common names: Drape Fin Barb, Indian Drape Fin Barb.
Size: 4-5cm
pH: 6.0 – 7.5
Tempº: 24ºC - 28ºC
Tank region: Middle Bottom layer
Origin: India, Burma.
Gender: Males have the spectacular large yellow dorsal fin, mature females are rounder and males tend to get larger and more colourful.
Notes: The Drape Fin Barb is still quite rare in the Aquarium trade, but when it is available it’s well worth snatching up. This peaceful schooling species can be quite shy, making it largely unsuitable for communities of big boisterous fish. It will enjoy a planted aquarium, where the school can seek refuge in the foliage. The fish will develop a pecking order between themselves – it’s usually a good idea to maintain them in a ratio of 1 male to every 2-3 females. This species will accept commercially prepared foods,

Blub

Congo Barb
(Clypeobarbus congicus)

Common names: Congo Barb.
Size: 6cm
pH: 6.0 – 7.0
Tempº: 22ºC - 26ºC
Tank region: Middle Bottom layer
Origin: Republic of Congo, Democratic Republic of Congo.
Gender: Males are more brightly coloured.
Notes: This species is rather unusual in the Aquatic Trade. It can be exceedingly shy when introduced to the Aquarium, so it is important to give it ample plant cover and lots of caves. They are a schooling species, and are quite peaceful. They are suitable for a community of other small, shy species but should not be housed with overly aggressive fish. The species in omnivorous, and will accept commercially prepared foods.

Blub

Common names: Golden Dwarf Barb, Geli Barb, Golden Barb, Dwarf Barb.
Size: 6cm
pH: 6.0 – 7.0
Tempº: 18ºC - 25ºC
Tank region: Middle Bottom layer
Origin: India, Bangladesh.
Gender: Males are smaller and have more intense colouration.
Notes: The Golden Dwarf Barb is a small, slightly sensitive Barb suitable for communities of small, peaceful fish. The Golden Dwarf Barb is a schooling species, and thus should be kept in groups of 6 or more. As with most small schooling species, it feels most comfortable in a Planted Aquarium with lots of cover. This species does not appreciate heavy currents, and will accept commercially prepared foods.

Blub

Common names: Snakeskin Barb, Rhomb Barb, Rhombo Barb.
Size: 5cm
pH: 5.0 – 7.0
Tempº: 23ºC - 28ºC
Tank region: Middle Bottom layer
Origin: Indonesia.
Gender: Males are smaller and have more intense colouration.
Notes: The exotic looking Snakeskin barb is quite hard to find in Fish Shops, but is much sought after by aquarists. It has a small size, peaceful temperament and beautiful markings. All Barbs need to be kept in schools of at least 6, and the Snakeskin is no exception. It will enjoy planted tanks which provide plenty of cover, and takes small flake and pellet foods.

Blub

Common names: Lemon Tetra, Lemon Fish.
Size: 5cm
pH: 5.5 – 7.5
Tempº: 22ºC - 28ºC
Tank region: Middle layer
Origin: Brazil.
Gender: The black line on the male’s anal fin is thicker and more distinct than that of the female.
Notes: The hardy Lemon Tetra is an exceedingly popular schooling fish for the community aquarium because of it’s small size and peaceful nature. The species is readily available, and will happily take commercially prepared foods. The Lemon Tetra has been in the hobby since 1932, yet still remains a firm favorite. As with most tetras, the lemon tetra appreciates a planted tank because of the cover provided by foliage. They can be kept in a moderate current, but certainly not a hillstream type environment.
Left Image: The Lemon Tetra is not as gaudy as it's Cardinal or Gold cousins, but is still beautiful fish for the planted aquarium.
Center Image: Lemon Tetras do not school as tightly as other Schooling species, but it is still important to maintain them in groups. Image credit to Jglove276 - thanks Jglove!
Right Image: This species is not an exceedingly fast swimmer, but does need space to explore. Photo credit goes to Jglove276.

FiremouthGuy

Common Names: Umbrella Cichlid
Size: Males 2.5 Inches, Females 2 Inches/ Males 6.25 cm, Females 5 cm.
pH: 5.5-7.0
Temp: 72-78 Fahrenheit/ 22-25 Degrees Celsius (Although they are found in waters with temps of 44 Degrees Fahrenheit! A very hardy fish when it comes to temperature. Avoid sudden changes of course, as always.)
Tank Region: Lower (Mine rarely swim without their pectoral fins skimming the substrate.)
Origin: South America
Gender: Males are more colorful and have longer pectoral/dorsal/anal fins. Females have orange belly at breeding time.
Notes: Like most Apistogrammas, these guys need harems or should be kept singly. Try to keep 2+ females for every male. Males defend the major area and females keep their little boundaries within that. Will not defile plants, and obviously is no big threat to decor with its diminutive size. In fact, they appreciate a heavily planted tank. Most say that these are very sensitive fish, but mine seem to do very well at 7.5 pH and 77 degrees.
These Apistogrammas exist in multiple color morphs in the wild, the blue-gold or gold, and the blue or opal.
Left Image: A stunning gold-morph male in aggressive display, spreading fins fully. Copyrighted Image Credit of dwarfcichlid.com . Thanks for the beautiful photo!
Right Image: Blue-morph male. Photo Credit of nicm.

FiremouthGuy

Common Names: Convict Cichlid, Zebra Cichlid
Size: 4 inches max/10 cm max
pH: 6-8
Temp: 68-82 Fahrenheit/ 20-28 Degrees Celsius
Tank Region: Mid-levels, Lower
Origin: Central America
Gender: Gender is almost all you need to breed these guys: Males are larger. Females are more colorful, with bright orange in the belly. The males sometimes develop a lump on the forehead and longer fins.
Notes: Relatively small size, beautiful coloration, super easy to breed, quite hardy; what not to like about these guys? Well they do have a downside. Convicts are super aggressive. While you might get away with one female in a community of larger fish, you most likely will need a pair only or species tank for them. They breed easily, but defend their brood fiercely, and will kill nearly any fish that is not tougher than them. Convicts have picked fights with Oscars twice their size, and won. Be cautious about where you put them.

Blub

Common names: Slender Hemiodus, Red-Tailed Hemiodus, Redtail Hemiodus.
Size: 15cm
pH: 5.8 – 7.2
Tempº: 22ºC - 27ºC
Tank region: Middle layer.
Origin: Brazil, Guyana, Venezuela.
Gender: Unknown.
Notes: This unusual Characin has not been bred in Aquariums, and most imports come from the wild. As a consequence, the Slender Hemiodus can be quite delicate. As with most characins, this species needs to be kept in a school, and because of the fish’s size and active nature will need a large aquarium. They can be a bit skittish when first introduced to an Aquarium, but in bigger numbers and with time they will become more adventurous. They are a very peaceful species, accepting a variety of foods, but Live food is a firm variourite. It is possible to keep Hemiodus in a community aquarium, although it’s size may spook smaller species. This fish is by no means a beginner fish, but with the right tank size and good water conditions the Slender Hemiodus can be truly appreciated.

Blub

Common names: Western Rainbowfish, Red tailed Rainbowfish, Westralian Sunfish.
Size: 10-12cm
pH: 6.5 – 8.0
Tempº: 22ºC - 27ºC
Tank region: Middle layer.
Origin: Western Australia
Gender: Similar to many other Rainbowfishes. Mature males tend to be more colourful and have deeper bodies and larger fins when full grown.
Notes: The Western Rainbowfish is not seen in the Aquarium trade as often as other rainbowfishes, like the Boesemani's or Praecox. However it has similar care requirements to other large rainbowfishes. This fish is a schooling species so should always be kept in groups; preferably with more females than males. Because of their size and boisterous activity, a large aquarium is required to happily house a school of Western Rainbowfish. They are very peaceful towards other fish, and make a good addition to a larger community. However, the Western Rainbowfish's size can spook some smaller and more skittish fish like Tetras so it is reccomended that these rainbowfish are not kept with tankmates much smaller than themselves. Good tankmates include larger Tetras, Barbs, Cordydoras catfish, Dwarf Plecos and Livebearers. This species is quite adaptable in terms of Water quality, so it should not be hard to provide a good pH and temperature for them. As with most rainbowfish, this species needs plenty of open space to swim but also appreciates plants to provide a peaceful retreat. In the wild, Western Rainbowfish colouration can vary with each population. Western Rainbowfish are not picky about food, and thus should take most commercially available fish diets. There have also been reports of this fish eating duckweed - a true bonus for some aquarists! Overall this is a very good, adaptable large community fish that doesn't come up very often but when it does it is well worth a purchase.

Blub

Common names: Zodiac Loach, Batik Loach
Size: 5.8cm
pH: 7.0 – 7.5
Tempº: 18ºC - 26ºC
Tank region: Bottom Layer
Origin: India
Gender: Unknown.
Notes: This is a rather rare species in the Aquarium Trade, but is an excellent fish to keep nonetheless. The Zodiac loach originated from clear, well oxygenated and fast flowing hillstreams and it's tank should be set up acordingly. This means fast flowing clean water and plenty of rocks and hiding places. Unlike most loaches, the Zodiac Loach is territorial to it's own species and thus it can be difficult to keep more than one Zodiac loach in an aquarium together. It is possible however, but there must be plenty of hiding places and lots of floor space in the tank. If this is kept in mind whilst designing the tank, then it should be possible to keep a small group of Zodiac Loaches. Good tankmates for the Zodiac loach include Danios, Minnows and small Barbs but in general small peaceful fish should coexist with the Zodiac happily as long as they have the same tank requirements. Unfortunately they have been reported as fin nippers, and as most long finned fishes tend to prefer slower moving waters anyway it is probably not a good idea to combine them with these loaches. This species is omnivorous and should take most commercially produced aquarium foods; preferably bottom sinking pellets. This species is rewarding for those prepared to provide appropriate conditions, but for a general community environment there are better loaches available.

Blub

Common names: Swallow-Tail Glass Catfish, Swallow Tailed Catfish, Three Striped African Glass Catfish, Debauwi Catfish.
Size: 8cm
pH: 6.0 – 7.5
Tempº: 23ºC - 28ºC
Tank region: Middle Layer
Origin: Nigeria, Niger, Mali, Guinea, Benin.
Gender: Females are usually slightly plumper than males.
Notes: Unlike most Catfishes, the Swallow-Tail Glass Catfish is a middle dwelling species. It is both extremely active and very peaceful, making a perfect candidate for the community aquarium. The Swallow-Tail is a schooling species, so must always be kept in groups of preferably 6 or more. They enjoy a planted aquarium but also need lots of free swimming space because they are incredibly active. This catfish is omnivorous and will readily consume aquarium flakes or similar commercially prepared foods. This species is sometimes known as the 'Dewaubi Catfish'; in reference to a very similar species called 'Pareutropius debauwi' but this species is actually rarely imported and fish sold as P.dewaubi are usually P.buffei. Overall this is an unusual but peaceful schooling fish ideal for community aquaria.