Bacopa Caroliniana: Caring For This Amazing Beginner Plant

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bacopa carolinia

Bacopa caroliniana grows everywhere – from soil to sandy aquariums, and there really isn’t a condition it won’t thrive in. You can use almost any substrate, lighting, or water parameters to grow it. It can be left floating and it’ll even survive brackish water conditions.

It does best in taller tanks because it grows so quickly, but you can grow it in shorter tanks – it just overtakes them much faster. Lemon bacopa works well for hiding equipment, creating territories for fish, or hiding spots for fry.

Like moneywort, Bacopa Caroliniana is technically a flowering herb and typically grows on land. It’s also called water hyssop, blue water hyssop, giant red bacopa, lemon bacopa, or giant red bacopa. 

lemon bacopa flower

What you may not know, is that scientists are currently attempting to make this plant bioluminescent. The goal is to use bacopa, and other plants and trees, to create environmentally-friendly street lights that would reduce energy costs, improve air quality, and keep the streets safely lit at night.

But back to your aquarium. It makes a fantastic addition to almost any tank for any skill level, so if you’re thinking about grabbing some for your tank, here’s how to take care of it.

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Table of contents

lemon bacopa care


Distribution & Natural Habitat

Bacopa carolinana is native to several states in the US. You can find them in wetlands, marshes, ponds, and lakes. typically, you’ll find them in areas where the water is 3′ deep or less, but it’ll also grow completely out of the water around the shorelines.

bacopa caroliniana wild

It’s hardy in USDA zones 6a – 9b, but you may find it in 5 zones as well.

Aquarium Care

Difficulty: Bulletproof
Size: 2’+ (61 cm)
Propagation: Side shoots, clippings
Fertilizer: Liquid, but substrate helps
Speed Of Growth: Rapid
Temperature: 58 – 90 F (14 – 32C)

pH5.0 -9.0
Hardness: 5 – 20 dKH
Placement: Background, floating
Origin: US
Aquascaping: Not usually used
Availability: Very common

Full transparency – I’ve managed to almost kill Bacopa Caroliniana several times and it always bounces back within a week. The biggest thing I’ve noticed with bc is that it doesn’t do well with floating plants blocking the light and it’s difficult to keep planted.

Without plant weights it floated on me pretty much constantly.


Bacopa caroliniana doesn’t need any special or high powered lights, but it does best when other plants aren’t blocking it. I would call it a moderate light plant. It does change colors and the stem structure based on the level of light it receives as well.

Under high light conditions, it turns pinkish to red/brown (hence the moniker “giant red bacopa.”) It’s leaves also grow in tighter clusters, making it bushy. Under lower light conditions, it turns bright green and the leaves grow farther apart.

bacopa caroliniana leggy

It can certainly become leggy under incredibly low-light conditions, and it’ll take a lot of careful trimming and a few months to get it back to its bushy self, so I suggest over lighting before under.

If you’d like more detailed information or more heaters to look at, you can check my detailed review of the best aquarium heaters.

Fertilizers & Substrates

Bc doesn’t need any special substrates, fertilizers, or Co2 either. I did have more success planting it in a plant substrate than I did in sand, gravel, or pebbles, but it survived and grew no matter what I planted it in. So if you’re going for seriously dense growth, I’d recommend a planted substrate and some liquid fertilizers over sand.

It can also be grow floating, but it doesn’t look great and I don’t know that I’d recommend it. 

bacopa caroliniana floating

If you opt for sand or another substrate without fertilizers in it, I would suggest buying a liquid fertilizer to add on a weekly basis. I have the best options for fertilizer substrate and liquid fertilizers below for you.

Common Problems

Bacopa caroliniana is probably one of the most fuss-free plants that I can think of. Not only is the least fussy plant in terms of water parameters, lighting, soil, – or if it’s even in water at all – but it also comes in with very few and far between issues.


plant melting

Melting is incredibly common in aquatic plants as most of them are grown above water. If you pluck off the dying parts of the plant before they start rotting, the new aquatic growth should appear soon enough, and it’ll do just fine.

Rapid Growth

fast plant growth problem

While rapid plant growth is a great thing in most cases, it can also become a problem when it comes to regular upkeep on trimming, nutrients, and excess plant disposal. Since fast-growing plants usually present an issue for local waterways and most are considered to be invasive species, taking care to properly dispose of excess is incredibly important.

In addition, it’s quite possible that it can choke out your other plants by out-competing them for nutrients. This can, of course, be remedied by changing the water more frequently, adding more fertilizer to the water, or keeping up on trimming of the faster-growing plants. But, since trimming and disposal also comes with its own issues, this last option is probably the most time-consuming.

Lack Of Nutrients

aquarium plant deficiencies

Fast-growing plants can cause two – er, maybe three – major nutrient issues.

  1. They can choke out other plants by out-competing them for nutrients. Eventually, the plants that can’t compete will slowly die. 
  2. They can soak up so many nutrients that they choke themselves out.
  3. They can out-compete your fish for the same nutrients in the water – especially fry. 

You can fix this issue by doing more water changes to replace nutrients or you can add fertilizers to the water to similarly replace nutrients. Although, both methods will require some tinkering and fine-tuning to get right.

Bacopa Caroliniana Maintenance

Maintenance for Bacopa Caroliniana is basically nonexistent. You may have to replant it from time to time if it floats up and, at some point, you’re definitely going to want to trim it. But other than that, you can leave it alone.

If you want to get the best growth out of it, or if you’re going for a specific look, you’re going to want to dose fertilizers weekly (or with every water change) and be a little more attentive with the level of lights and pruning. 

Disposing of unwanted Bacopa Caroliniana is probably the most challenging part. Preventing lemon bacopa from getting into local waterways – even if it’s native to where you live – is important for the balance of the local ecosystems. This is particularly true for those who live near wetlands.

You can bury lemon bacopa (even in your garden for nutrients like you can with hornwort,) add it to your compost heap, or use a bleach soak to kill it before throwing it away (or soak it long enough to dissolve it in bleach.)

If that all sounds like too much, you can throw it away in plastic bags to prevent it from getting into local water bodies – although, then you may be introducing more plastic waste into waterways and oceans.

Propagating Bacopa Carolinia

Once you let your lemon bacopa grow long enough, it’ll start sending off side shoots or pseudo runners where new stems will grow. If you’re antsy, or if it’s getting too tall for your tank, you can clip it where the new roots are starting to form on the stem and plant those clippings.

If no pieces on your stem have roots yet, don’t worry, you can still clip a piece off and leave the piece to float until roots develop. Once the roots have developed, you can plant it without fear of it rotting. If you try to plant it before any roots form, your new clipping will likely rot.

What About Fish?

I’m usually the first person to tell you not all fish do well with all plants… but since lemon bacopa does well in almost any environment, floating or not, low pH, high pH, any substrate, any temperature range, and most fish won’t eat it… there’s really not a fish I can think of that shouldn’t do just fine. Which is a rare thing, indeed!

Further Reading & Resources

IFAS – Lemon Bacopa

Nature Serve – Bacopa Caroliniana

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