Compatibility brief
Can Guppy live with Jack Dempsey?
Risky. This mix is commonly discouraged for typical setups.
Compatibility score
Profile confidence: medium
How we decideFishori checks adult size and predation risk, behaviour, water requirements and tank needs before giving a verdict.
200L
Combined minimum footprint reference for these two species: about 200L (larger active fish often want more length).
Jack Dempsey (about 25cm as an adult) can realistically eat Guppy (about 5cm) once grown. Plan around adult sizes, not shop sizes.
Guppy (peaceful) and Jack Dempsey (aggressive) are far apart on aggression — bullying or injury is a common outcome in average community layouts.
Assessment details
Aggression mismatch
Top issueJack Dempsey is aggressive, while Guppy is peaceful. The aggressive fish will likely bully or harm the peaceful one.
Jack Dempsey may eat Guppy
Jack Dempsey (25cm) is predatory and Guppy (5cm) is small enough to be eaten. This pairing is unsafe.
Compatible temperature range
Both fish can comfortably share similar water temperatures.
“Jack Dempsey is aggressive, while Guppy is peaceful”
Aggression mismatch
Next steps
Concrete changes, not "research more" filler.
Try instead
- →Build a species-only tank for the larger fish, or restock with fish too large to be eaten at adult sizes.
- Seriously Fish. Poecilia reticulata
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Poecilia reticulata
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Poecilia reticulata
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
- Wikipedia. Guppy
Encyclopaedia overview; use specialist aquarium sources for your stock's real temperature/pH/footprint needs.
- Seriously Fish. Rocio octofasciata
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Rocio octofasciata
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Rocio octofasciata
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
Try this next
Build the full stocking list with Guppy + Jack Dempsey
Plan further
Check each species’ mates list, size the glass, then verify the full stock in the builder. Methodology explains how verdicts are produced.
Individual fish vary in personality. Fishori uses conservative hobby rules. Observe any new introduction closely, feed thoughtfully, and keep a quarantine or backup plan. This is not veterinary advice.
Profile data confidence: high. Checked against several solid care sources that mostly agree.