Shoal & Stem

Species Catalogue

1,492 species — care guides, community photos, water parameters, and tank-mate compatibility.

plant
medium

Ludwigia Peruensis

Ludwigia peruensis

plantfreshwater
Background·Fast growth
plant
easy

Ludwigia Repens

Ludwigia repens

plantfreshwater
Background·Medium to high light·Moderate growth
plant
easy

Ludwigia Rubin

Ludwigia repens 'Rubin'

plantfreshwater
Background·Fast growth
plant
hard

Ludwigia Senegalensis

Ludwigia senegalensis

plantfreshwater
Midground·Slow growth
plant
medium

Ludwigia Super Red

Ludwigia sp. 'Super Red'

plantfreshwater
Background·High light·Moderate growth
plant
medium

Ludwigia Super Red Mini

Ludwigia sp. 'Super Red Mini'

plantfreshwater
Midground·High light·Moderate growth
plant
hard

Ludwigia White

Ludwigia palustris 'White'

plantfreshwater
Midground·Slow growth
plant
easy

Ludwigia sp. Red

Ludwigia sp. 'Red'

plantfreshwater
Background·Fast growth
algae
hard

Lyngbya

Lyngbya sp.

algaefreshwater

Dark, wiry filaments of cyanobacteria that form dense mats — often mistaken for BBA. Unlike true algae, it can fix atmospheric nitrogen, meaning low nitrogen levels do not suppress it. Produces toxins harmful to invertebrates. Requires the same treatment as blue-green algae: blackout, H₂O₂ treatment, and improved flow.

fish
medium

Lyretail Anthias

Pseudanthias squamipinnis

fishsaltwater
5″·75+ gal·group 5+·peaceful
fish
easy

Lyretail Guppy

Poecilia reticulata

fishfreshwater
2″·10+ gal·group 3+·peaceful
fish
easy

Lyretail Molly

Poecilia sphenops

fishfreshwater
3″·20+ gal·group 3+·peaceful
fish
easy

Lyretail Swordtail

Xiphophorus hellerii

fishfreshwater
4.5″·20+ gal·group 3+·peaceful
fish
easy

Macropterus Corydoras

Corydoras macropterus

fishfreshwater
3″·20+ gal·group 4+·peaceful
plant
hard

Madagascar Lace Plant

Aponogeton madagascariensis

plantfreshwater
Moderate growth
fish
medium

Madagascar Rainbow

Bedotia geayi

fishfreshwater
3.5″·40+ gal·group 6+·peaceful
snail
easy

Magenta Mystery Snail

Pomacea bridgesii

snailfreshwater
2″·5+ gal·peaceful
algae
medium

Maiden's Hair

Chlorodesmis fastigiata

algaesaltwater

Vivid blue-green turf-like tufts of very fine filaments — a common sight on Indo-Pacific reefs. In captivity it can spread across rockwork quickly. Produces terpene compounds that deter most grazers. Interesting as a biotope element but can become a nuisance if left unchecked.

fish
medium

Maingano

Melanochromis cyaneorhabdos

fishfreshwater
3.5″·40+ gal·aggressive
fish
easy

Malabar Danio

Devario malabaricus

fishfreshwater
3.5″·20+ gal·group 6+·peaceful
shrimp
medium

Malaya Shrimp

Caridina malayensis

shrimpfreshwater
1.2″·5+ gal·group 10+·peaceful
fish
expert

Mandarin Dragonet

Synchiropus splendidus

fishsaltwater
3″·30+ gal·peaceful
fish
medium

Marble Angelfish

Pterophyllum scalare

fishfreshwater
6″·30+ gal·group 2+·semi-aggr.
fish
easy

Marble Betta

Betta splendens 'Marble'

fishfreshwater
2.5″·5+ gal·semi-aggr.
fish
easy

Marble Molly

Poecilia sphenops

fishfreshwater
3″·20+ gal·group 3+·peaceful
plant
easy

Marble Queen Sword Mini

Echinodorus cordifolius 'Mini'

plantfreshwater
Midground·Slow growth
fish
medium

Marbled Hatchetfish

Carnegiella strigata

fishfreshwater
1.5″·15+ gal·group 6+·peaceful
fish
medium

Marbled Headstander

Abramites hypselonotus

fishfreshwater
3.5″·30+ gal·group 4+·peaceful
fish
hard

Marbled Sleeper Goby

Oxyeleotris marmorata

fishfreshwater
24″·200+ gal·aggressive
snail
easy

Margarita Snail

Margarites pupillus

snailsaltwater
1″·10+ gal·peaceful
fish
easy

Marigold Platy

Xiphophorus maculatus

fishfreshwater
2.5″·10+ gal·group 5+·peaceful
algae
easy

Marimo Moss Ball

Aegagropila linnaei

algaefreshwater

Beloved velvety-green spheres of filamentous green algae — not a moss at all. Forms naturally in cold lakes where wave action rolls colonies into balls over decades. A low-maintenance aquarium icon that grows extremely slowly. Rotate occasionally for even light exposure.

fish
medium

Marlier's Julie

Julidochromis marlieri

fishfreshwater
3.5″·30+ gal·semi-aggr.
invertebrate
easy

Marmorkrebs Crayfish

Procambarus virginalis

invertebratefreshwater
1.5″·10+ gal·semi-aggr.
fish
easy

Maroon Clownfish

Premnas biaculeatus

fishsaltwater
6″·30+ gal·group 2+·aggressive
plant
easy

Marsilea Crenata

Marsilea crenata

plantfreshwater
Carpet·Medium to high light·Medium growth