Shoal & Stem

Species Catalogue

1,570 species — care guides, community photos, water parameters, and tank-mate compatibility.

fish
easy

Blind Cave Tetra

Astyanax mexicanus

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

Blue Acara

Andinoacara pulcher

fishfreshwater
7″·55+ gal·semi-aggr.
fish
easy

Blue Assessor

Assessor macneilli

fishsaltwater
2.5″·20+ gal·peaceful
fish
medium

Blue Axelrodi Rasbora

Sundadanio axelrodi blue

fishfreshwater
1.2″·10+ gal·group 8+·peaceful
fish
medium

Blue Badis

Badis badis

fishfreshwater
1″·10+ gal·peaceful
shrimp
hard

Blue Bolt Pinto Shrimp

Caridina logemanni

shrimpfreshwater
1.25″·10+ gal·group 10+·peaceful
fish
hard

Blue Diamond Discus

Symphysodon sp.

fishfreshwater
6″·55+ gal·group 4+·peaceful
fish
easy

Blue Gourami

Trichopodus trichopterus

fishfreshwater
5″·20+ gal·semi-aggr.
fish
medium

Blue Gularis Killifish

Fundulopanchax sjoestedti

fishfreshwater
4″·20+ gal·semi-aggr.
shrimp
hard

Blue King Kong Shrimp

Caridina logemanni

shrimpfreshwater
1.5″·10+ gal·group 10+·peaceful
shrimp
hard

Blue Leg Poso Prawn

Macrobrachium latidactylus

shrimpfreshwater
2.5″·20+ gal·semi-aggr.
fish
easy

Blue Medaka

Oryzias latipes

fishfreshwater
1.5″·10+ gal·group 6+·peaceful
invertebrate
medium

Blue Moon Crayfish

Cherax pulcher

invertebratefreshwater
5.5″·30+ gal·semi-aggr.
fish
easy

Blue Panchax

Aplocheilus panchax

fishfreshwater
3″·15+ gal·peaceful
shrimp
easy

Blue Pearl Shrimp

Neocaridina zhangjiajiensis var. Blue Pearl

shrimpfreshwater
1.2″·5+ gal·group 6+·peaceful
fish
medium

Blue Phantom Pleco

Hemiancistrus sp.

fishfreshwater
6″·40+ gal·semi-aggr.
shrimp
hard

Blue Pincher Macro

Macrobrachium vollenhovenii

shrimpfreshwater
5.9″·40+ gal·aggressive
fish
easy

Blue Platy

Xiphophorus maculatus

fishfreshwater
2.5″·10+ gal·group 3+·peaceful
shrimp
easy

Blue Rili Shrimp

Neocaridina davidi

shrimpfreshwater
1.5″·5+ gal·group 10+·peaceful
fish
easy

Blue Star Endler

Poecilia wingei

fishfreshwater
1.2″·5+ gal·group 3+·peaceful
fish
medium

Blue Tang

Paracanthurus hepatus

fishsaltwater
12″·100+ gal·semi-aggr.
shrimp
hard

Blue Tiger Shrimp

Caridina cf. cantonensis 'Blue Tiger'

shrimpfreshwater
1.2″·5+ gal·group 6+·peaceful
fish
easy

Blue Wag Platy

Xiphophorus maculatus

fishfreshwater
2.5″·10+ gal·group 3+·peaceful
algae
hard

Blue-Green Algae (Freshwater)

Cyanobacteria spp.

algaefreshwater

A blue-green or red-brown slime that coats the substrate, plants, and glass with a slimy, foul-smelling mat. Technically a bacterium, not true algae. Caused by low nitrates, poor flow, and organic waste. Responds to a 3-day blackout combined with the antibiotic erythromycin or hydrogen peroxide treatment.

algae
hard

Blue-Green Algae (Saltwater)

Cyanobacteria spp.

algaesaltwater

Red, purple, or dark blue-green slime mats that smother the sandbed and rockwork with a slimy, oxygen-depleting film. Technically a bacterium. Caused by low nitrates, poor flow, and high dissolved organics. A 3-day blackout, hydrogen peroxide spot-treatment, and improved flow usually break the cycle.

fish
easy

Blue-throat Triggerfish

Xanthichthys auromarginatus

fishsaltwater
12″·75+ gal·semi-aggr.
snail
easy

Blueberry Snail

Viviparus sp.

snailfreshwater
0.75″·5+ gal·peaceful
fish
easy

Bluefin Killifish

Lucania goodei

fishfreshwater
1.5″·5+ gal·peaceful
fish
medium

Bluefin Notho

Nothobranchius rachovii

fishfreshwater
2.5″·10+ gal·group 2+·semi-aggr.
fish
medium

Blushing Angelfish

Pterophyllum scalare

fishfreshwater
6″·30+ gal·group 2+·semi-aggr.
plant
medium

Blyxa Aubertii

Blyxa aubertii

plantfreshwater
Midground·Medium growth
fish
medium

Borellii Dwarf Cichlid

Apistogramma borellii

fishfreshwater
2.5″·20+ gal·semi-aggr.
fish
medium

Borneo Sucker Loach

Gastromyzon punctulatus

fishfreshwater
2″·20+ gal·group 3+·peaceful
invertebrate
easy

Brazos Dwarf Crayfish

Cambarellus texanus

invertebratefreshwater
1.4″·10+ gal·peaceful
fish
medium

Brevis Shell Dweller

Neolamprologus brevis

fishfreshwater
1.5″·20+ gal·semi-aggr.
fish
medium

Brichardi Cichlid

Neolamprologus brichardi

fishfreshwater
4″·30+ gal·group 2+·semi-aggr.