Best for 20-Gallon Tanks
Community favorites that need a bit more swimming room.
Neon Tetra
Paracheirodon innesi
70-81°FpH 6-710+ gallons
Peacefulschooling 6+1.5"
Cardinal Tetra
Paracheirodon axelrodi
73-81°FpH 4.5-6.510+ gallons
Peacefulschooling 6+2"
Ember Tetra
Hyphessobrycon amandae
73-84°FpH 5.5-75+ gallons
Peacefulschooling 8+0.8"
Rummy Nose Tetra
Hemigrammus rhodostomus
75-84°FpH 5.5-720+ gallons
Peacefulschooling 6+2.5"
Black Neon Tetra
Hyphessobrycon herbertaxelrodi
73-81°FpH 5.5-7.510+ gallons
Peacefulschooling 6+1.6"
Serpae Tetra
Hyphessobrycon eques
72-82°FpH 6-7.520+ gallons
Semi-aggressiveschooling 6+1.75"
Black Skirt Tetra
Gymnocorymbus ternetzi
70-82°FpH 6-7.515+ gallons
Peacefulschooling 5+3"
Betta Fish
Betta splendens
76-82°FpH 6.5-7.55+ gallons
Semi-aggressive3"
Guppy
Poecilia reticulata
72-82°FpH 6.8-7.810+ gallons
Peacefulschooling 3+2.5"
Endler's Livebearer
Poecilia wingei
72-82°FpH 6.5-85+ gallons
Peacefulschooling 3+1.5"
Platy
Xiphophorus maculatus
70-80°FpH 7-810+ gallons
Peacefulschooling 3+3"
Molly
Poecilia sphenops
72-82°FpH 7-8.520+ gallons
Peacefulschooling 3+4.5"
Swordtail
Xiphophorus hellerii
72-82°FpH 7-8.520+ gallons
Peacefulschooling 3+5.5"
Panda Corydoras
Corydoras panda
68-77°FpH 6-7.510+ gallons
Peacefulschooling 6+2"
Julii Corydoras
Corydoras julii
72-79°FpH 6-7.510+ gallons
Peacefulschooling 6+2.5"
Sterbai Corydoras
Corydoras sterbai
75-82°FpH 6-7.515+ gallons
Peacefulschooling 6+2.75"
Bristlenose Pleco
Ancistrus cirrhosus
72-82°FpH 6-7.520+ gallons
Peaceful5"
Otocinclus Catfish
Otocinclus vittatus
72-79°FpH 6-7.510+ gallons
Peacefulschooling 4+2"
Kuhli Loach
Pangio kuhlii
75-86°FpH 5.5-715+ gallons
Peacefulschooling 5+4"
Cherry Shrimp
Neocaridina davidi
65-80°FpH 6.5-85+ gallons
Peacefulschooling 6+1.5"
Amano Shrimp
Caridina multidentata
68-80°FpH 6.5-7.510+ gallons
Peacefulschooling 4+2"
Nerite Snail
Neritina natalensis
72-78°FpH 7-8.55+ gallons
Peaceful1"
Mystery Snail
Pomacea bridgesii
68-82°FpH 7-85+ gallons
Peaceful2.5"
Harlequin Rasbora
Trigonostigma heteromorpha
72-81°FpH 6-7.510+ gallons
Peacefulschooling 6+2"