Guppy vs Platy

The same axes for both animals, taken from the same care guides, so this is a like-for-like comparison rather than two articles written months apart. Neither animal is the right answer on its own — the question is which one fits the space, the budget and the routine you actually have.

Freshwater Fish
Guppy
Poecilia reticulata
Difficulty
Beginner
Lifespan
2-3 years
Adult size
3-6cm / 1.5-2.5in
Minimum space
38 L (10 US gal)
Company
Must be kept in at least 3
Daily time
10-15 min daily; weekly water change
Running cost
Low
Habitat
Aquarium 38L+ / 10gal+, heated and filtered
Diet
Omnivore (flake, micro-pellet, veg, live foods)
Suits you if
Absolute beginners and children's first tanks. Community aquariums with peaceful species. Keepers who enjoy colour and breeding
Watch out for
Unplanned breeding overwhelming the tank. Buying weak, mass-bred stock prone to disease. Keeping males with too few females

Full Guppy guide

Freshwater Fish
Platy
Xiphophorus maculatus
Difficulty
Beginner
Lifespan
3-4 years
Adult size
4-6cm / 1.5-2.5in
Minimum space
57 L (15 US gal)
Company
Must be kept in at least 3
Daily time
10-15 min daily; weekly water change
Running cost
Low
Habitat
Aquarium 57L+ / 15gal+, heated and filtered
Diet
Omnivore (flake, pellet, veg, live foods)
Suits you if
Beginner community aquariums. Keepers wanting hardy, colourful fish. Children's first properly set-up tanks
Watch out for
Keeping in soft, acidic water. Overfeeding leading to obesity and constipation. Unplanned breeding from mixed-sex groups

Full Platy guide

How to read this

Every row is filled from the same field of the same care guide for both animals, so nothing here is cherry-picked to favour one of them.

Minimum space is the figure from each species' housing guidance, converted to one unit. It is a floor, not a target.

What this does not tell you: your experience, your household, your climate, or which animal you will actually enjoy. Difficulty is our judgement, not a measurement. Read both full guides before deciding — and if the honest answer is neither, that is a good outcome too.