Encyclopaedia

FishFreshwaterAdvanced

Lamontichthys

Lamontichthys filamentosus

A silvery 15-20 cm algae-eater known for the extensive filaments of its fins. Lives in turbulent and pristine waters, constantly feeds on biofilm. Very rare.

Taxonomy
Class:Actinopteri
Order:Siluriformes
Family:Loricariidae
Subfamily:Loricariinae
Genus:Lamontichthys
Species:Lamontichthys filamentosus

Share

Check out Lamontichthys on Atlarium

PracticeRecognition quizzesPhotos, names, origins, and puzzles to review Atlas species.Open quizzes
Water Temperature

24 - 28 °C

pH Value

6 - 7.2

Water type

Freshwater

Tank level

Bottom

Adult size

20 cm

Minimum tank volume

>= 180 L

Minimum group

>= 1

GH

1 - 10 dGH

KH

1 - 5 dKH

TDS

25 - 200 ppm

Conductivity

39 - 313 uS/cm

Species description

Geographical Origin and Habitat: Upper Amazon Basin (Peru, Brazil). Lives in rivers (White and Clear water) characterized by very strong currents, sandy/pebbly bottoms and extremely high oxygen saturation.
Taxonomy and Morphology: Filament Loricaria (Lamontichthys filamentosus). Amazing Loricariid with a flattened and extremely elongated body. The main feature are the first rays of the pectoral, dorsal and upper caudal lobe fins which extend into very long filaments.
Social Behavior: Totally inoffensive and peaceful, both with other species and with conspecifics. Unlike many loricariids, it is not a cave-dwelling loner but prefers to station in groups on woods lapped by the strong current.
Coloration and Sexual Dimorphism: Light sand-brown base (perfect camouflage on the bottom), often with a delicate checkered or vermiculated pattern along the back. Sexually mature males develop odontodes ("fuzz") on the margins of the head.

Care, breeding and tankmates

Aquarium Setup: Stream fish tank (River manifold/Hillstream). Very fine sand, rounded river pebbles, sunken smooth woods. One or more oversized wavemakers (continuous uni-directional flow) are categorically required.
Diet and Feeding: Herbivore/Aufwuchs gleaner. In nature it scrapes the organic film (algae and micro-organisms) on stones exposed to the current. Provide sinking spirulina tablets, raw zucchini, and occasionally frozen bloodworms.
Water Quality: Extreme cleanliness requirements. Intolerant to ammonia and nitrites (tolerates nitrates only < 10ppm). The water must be hyper-oxygenated; a drop of O2 in the tank will be fatal in a few hours.
Compatibility and Cohabitation: Do not insert in generic community aquariums. Excellent with current-loving fish such as small stream Characins, Corydoras (e.g. arcuatus), and Sturisoma. Avoid aggressive cichlids that would damage its delicate filaments.
Aquarium Breeding: Rare. Open surface spawners: they lay a cluster of large amber eggs on smooth surfaces (e.g. glass or large leaves) in a strong current. The male takes care of ventilation until hatching.
Risks and Diseases: Starvation due to immature tank. Often imported wild, they struggle to recognize industrial feeds. If placed in sterile tanks without a consolidated algal carpet on the glass, they will starve within a month.

Geographic Origin and Distribution

Upper Amazon Basin (Peru, Brazil). Lives in rivers (White and Clear water) characterized by very strong currents, sandy/pebbly bottoms and extremely high oxygen saturation.

Origin

Tropical oceans and reefsAmazon, Orinoco, and Guianas

Fish profile

Temperament
Semi-aggressive
This is a profoundly peaceful and somewhat reclusive fish that focuses entirely on grazing. They are highly sensitive to deteriorating water conditions and aggressive tank mates. Providing a specialized riverine setup will ensure they remain active, healthy, and visible.
Diet
Omnivore
They are specialized aufwuchs grazers that feed heavily on biofilm, algae, and micro-organisms growing on hard surfaces. In the aquarium, their diet must be supplemented with high-quality algae wafers, spirulina, and fresh blanched vegetables. Occasional meaty foods like frozen bloodworms can be offered sparingly as a treat.
Sex ratio
Specific M:F ratio
They are generally indifferent to conspecifics, and sex ratios are not a major concern in the aquarium. Multiple individuals can be kept together if the tank is large enough to provide ample grazing surfaces. Territorial disputes between males are incredibly rare and mostly involve harmless displays.
Feeding frequency
Twice daily
Because they are continuous grazers, food should always be available in the form of biofilm or sinking wafers. Dropping food into the tank daily, preferably just before lights out, aligns with their nocturnal foraging habits. Ensure they are actively eating, as they can easily starve in newly established aquariums.
Bioload
This large loricariid produces a significantly high bioload due to its constant grazing and robust metabolism. Powerful biological filtration and excellent oxygenation are absolutely crucial to handle their waste. Frequent, substantial water changes are required to keep nitrates low and maintain their health.
Flow
Stagnant
Originating from fast-flowing rivers, they absolutely demand a very strong current and highly oxygenated water. Powerheads or specialized river-manifold systems are required to replicate their natural habitat. Inadequate flow will quickly lead to lethargy, stress, and eventual death.
Reproduction
Oviparous
Breeding in captivity is exceptionally rare and poorly documented for this specific species. They are presumed to be cave or crevice spawners like many related loricariids. Replicating highly specific seasonal changes in water temperature and flow is likely necessary to induce spawning.
Compatibility & tankmates
They are remarkably peaceful towards other fish and ignore most tank mates completely. They can be kept with medium to large peaceful community fish that appreciate similar high-flow environments. Avoid highly aggressive bottom-dwellers that might compete with them for grazing territory.
Tank level
Bottom
They are almost exclusively bottom-dwellers that cling to rocks, driftwood, and the aquarium glass. They rely heavily on their specialized suckermouths to anchor themselves in strong currents. They will rarely, if ever, venture into the open middle or upper water column.

Window to the official scientific data of the species

Data synced on: 06/15/2026

Scientific Parameters & Models

Trophic level
2.5 ± 0.2 se
Resilience
Medium (1.4 - 4.4 years)
Phylogenetic uniqueness (PD50)
0.5156
Bayesian Length-Weight
a = 0.00398, b = 3.11
VulnerabilityLow vulnerability (10 / 100)

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.

Related species

Recommendations grouped by close relatives, companion choices, and similar care.

Variants and close relatives

Same atlas type, nearby scientific identity, genus, or family.

Butterfly Pleco

Butterfly Pleco

Dekeyseria picta

View details->
Orinoco Twig Catfish

Orinoco Twig Catfish

Farlowella mariaelenae

View details->
Red Lizard Catfish (L010a)

Red Lizard Catfish (L010a)

Leliella sp.

View details->
Candy Stripe Pleco (L015)

Candy Stripe Pleco (L015)

Peckoltia vittata

View details->
Tentacle Lasiancistrus

Tentacle Lasiancistrus

Lasiancistrus tentaculatus

View details->
Marble Whiptail

Marble Whiptail

Loricaria simillima

View details->
Royal Pleco (L190)

Royal Pleco (L190)

Panaque nigrolineatus

View details->
Vampire Pleco (L029)

Vampire Pleco (L029)

Leporacanthicus galaxias

View details->
Twig Catfish (Farlowella)

Twig Catfish (Farlowella)

Farlowella acus

View details->
Gold Marble Bristlenose (LDA08)

Gold Marble Bristlenose (LDA08)

Ancistrus claro

View details->
Contradens Pleco

Contradens Pleco

Hypancistrus contradens

View details->
Bristlemouth Pleco

Bristlemouth Pleco

Peckoltia multispinis

View details->
Giant-eye Otocinclus

Giant-eye Otocinclus

Hypoptopoma gulare

View details->
Leopard Frog Pleco (L134)

Leopard Frog Pleco (L134)

Peckoltia compta

View details->
Medusa Pleco (L034)

Medusa Pleco (L034)

Ancistrus ranunculus

View details->
Zebra Pleco (L046)

Zebra Pleco (L046)

Hypancistrus zebra

View details->

Recommended companions

Compatible cards from coherent ecosystems with matching parameters.

Alternanthera reineckii "rosaefolia minor"
Plant

Alternanthera reineckii "rosaefolia minor"

Alternanthera reineckii "rosaefolia minor"

View details->
Ammannia mauritiana
Plant

Ammannia mauritiana

Ammannia mauritiana

View details->
Ammannia sp. 'Bonsai'
Plant

Ammannia sp. 'Bonsai'

Ammannia sp. 'Bonsai'

View details->
Arrowhead Anubias
Plant

Arrowhead Anubias

Anubias hastifolia

View details->
Blyxa alternifolia
Plant

Blyxa alternifolia

Blyxa alternifolia

View details->
Blyxa cf. vietii
Plant

Blyxa cf. vietii

Blyxa cf. vietii

View details->
Bacopa sp. "Japan"
Plant

Bacopa sp. "Japan"

Bacopa sp. "Japan"

View details->
Bolbitis heteroclita
Plant

Bolbitis heteroclita

Bolbitis heteroclita

View details->
Bucephalandra motleyana "Braun-rot narrow"
Plant

Bucephalandra motleyana "Braun-rot narrow"

Bucephalandra motleyana "Braun-rot narrow"

View details->
Bucephalandra motleyana "Riam Macam"
Plant

Bucephalandra motleyana "Riam Macam"

Bucephalandra motleyana "Riam Macam"

View details->
Bucephalandra motleyana "Braun-rot" ("Serimbu")
Plant

Bucephalandra motleyana "Braun-rot" ("Serimbu")

Bucephalandra motleyana "Braun-rot" ("Serimbu")

View details->
Bucephalandra motleyana "Kapit"
Plant

Bucephalandra motleyana "Kapit"

Bucephalandra motleyana "Kapit"

View details->
Bucephalandra motleyana "Pancuraji"
Plant

Bucephalandra motleyana "Pancuraji"

Bucephalandra motleyana "Pancuraji"

View details->
Bucephalandra sp. "Bukit Kelam / Sintang"
Plant

Bucephalandra sp. "Bukit Kelam / Sintang"

Bucephalandra sp. "Bukit Kelam / Sintang"

View details->
Bucephalandra sp. "Melawi"
Plant

Bucephalandra sp. "Melawi"

Bucephalandra sp. "Melawi"

View details->
Anubias
Plant

Anubias

Anubias barteri

View details->

Similar care

Cards with similar requirements, difficulty, habitat, and husbandry profile.

Guahibo Pleco

Guahibo Pleco

Hemiancistrus guahiborum

View details->
Meandrinus Pleco

Meandrinus Pleco

Hemiancistrus

View details->
Hi-Fin Green Phantom Pleco (L200)

Hi-Fin Green Phantom Pleco (L200)

Baryancistrus demantoides

View details->
Green Phantom Pleco

Green Phantom Pleco

Hemiancistrus subviridis

View details->
Big Spot Pleco (L075)

Big Spot Pleco (L075)

Hemiancistrus sabaji

View details->
Three Beacon Pleco (L091)

Three Beacon Pleco (L091)

Leporacanthicus triactis

View details->
Snowball Pleco

Snowball Pleco

Hypancistrus inspector

View details->
Golden Vampire Pleco

Golden Vampire Pleco

Leporacanthicus heterodon

View details->
Tapajós Royal Pleco (L027)

Tapajós Royal Pleco (L027)

Panaque armbrusteri

View details->
Ghost Pleco (L141/L215)

Ghost Pleco (L141/L215)

Hemiancistrus snethlageae

View details->
Para Pleco (L075)

Para Pleco (L075)

Ancistomus

View details->
King Tiger Pleco (L066)

King Tiger Pleco (L066)

Hypancistrus sp. L066

View details->
Monte Dourado Pleco (L411)

Monte Dourado Pleco (L411)

Hypancistrus sp. L411

View details->
Blue Panaque (L239)

Blue Panaque (L239)

Baryancistrus beggini

View details->
Queen Arabesque Pleco (L260)

Queen Arabesque Pleco (L260)

Hypancistrus sp. L260

View details->
White Seam Bristlenose (L059)

White Seam Bristlenose (L059)

Ancistrus hoplogenys

View details->
Last updated: 06/30/2026
Lamontichthys (Lamontichthys filamentosus) Care Guide & Tank Setup | Atlarium