Plant comparison
Bacopa Caroliniana vs Purple Bacopa
How the Bacopa Caroliniana and Purple Bacopa compare on care, size, water and temperament, and which plant suits your tank.
By Mike ElmiraUpdated
TL;DR, Bacopa Caroliniana vs Purple Bacopa
The Bacopa Caroliniana and the Purple Bacopa are close cousins, both in the Bacopa group, so at a glance they ask for a lot of the same things. Both are happy somewhere around 22 to 28 °C and pH 6 to 7.5, so a single tank can suit either one. The Bacopa Caroliniana is the more forgiving of the two, which matters if this is an early tank, while the Purple Bacopa rewards a bit more attention. In a low-tech, low-light setup the Bacopa Caroliniana is the safer bet; the other really wants brighter light to look its best.
Group compatibility overview
Excellent fit
Every key parameter overlaps and no major conflicts surfaced.
Temperature
- Bacopa Caroliniana18–28 °C
- Purple Bacopa22–28 °C
pH
- Bacopa Caroliniana6–8
- Purple Bacopa5.5–7.5
Hardness
- Bacopa Caroliniana3–18 dGH
- Purple Bacopa2–12 dGH
Full attributes
Every parameter, side by side| Parameter |  PlantBacopa CarolinianaBacopa caroliniana |  PlantPurple BacopaBacopa salzmannii |
|---|---|---|
| Category | Plant | Plant |
| Origin | Southeastern USA | South America |
| Family | Plantaginaceae | Plantaginaceae |
| Temperature | 18–28 °C | 22–28 °C |
| pH | 6.0–8.0 | 5.5–7.5 |
| Hardness (dGH) | 3–18 | 2–12 |
| Flow rate | Low to High | Low to Medium |
| Max height | 20–40 cm | 20–35 cm |
| Difficulty | 1 / 5 | 2 / 5 |
| Light | Low to High | Medium to High |
| CO₂ | Optional | Recommended |
| Growth rate | Medium | Medium |
Frequently asked questions
Direct answers to the questions search engines and AI assistants surface most often about this species.
Can you keep Bacopa Caroliniana and Purple Bacopa together?
Yes. Their temperature and pH ranges overlap around 22 to 28 °C and pH 6 to 7.5, so one set of water conditions keeps both comfortable. Match group sizes and cover the usual planted-tank basics and they share a tank fine.
Which is easier to keep, the Bacopa Caroliniana or the Purple Bacopa?
The Bacopa Caroliniana is the easier of the two, closer to very easy, while the Purple Bacopa leans beginner-friendly.
Do Bacopa Caroliniana and Purple Bacopa need the same water?
Close to it. Aim for 22 to 28 °C and pH 6 to 7.5 and you're in the shared sweet spot for both. Full ranges are in the table above.
What's the main difference between the Bacopa Caroliniana and the Purple Bacopa?
Placement and light. The Bacopa Caroliniana works as midground or background, the Purple Bacopa as background or midground, and their light needs differ, which is covered in the table.