Choosing the right plant for an aquarium can be a bit of a headache. Many have exacting demands in terms of lighting, nutrients, and temperature. And the most common low light plants are often slow growing and not as vibrant in color as high light plants.
That’s why I suggest looking at Moneywort, an amphibious plant that only needs a little extra TLC to thrive in most setups!
About Moneywort (Lysimachia nummularia)
The common names for Moneywort depend mostly on the use. When sold for herbal use it goes by medicinal or ayurvedic names like Brahmi. In the gardening and aquarium trade it is typically known as Moneywort or Creeping Jenny, due to its habit of growing horizontally along the water’s surface. These horizontal growths then extend vertical runners into the air where flowers form to attract pollinators.
As an adaptable wetland plant, Moneywort can be grown both in aquariums and Paludariums combining submerged and emersed zones. And if you’re a fan of herbal medicine Moneywort is considered a cure-all within several traditions.
For example, in European folk medicine, Moneywort was used for ulcers, stomach upset, sores, and hemorrhages. While the many medicinal benefit claims are rather diverse there are ongoing clinical trials that suggest the plant does have a positive effect on memory and cognitive function. Moneywort extracts are a popular nootropic for boosting brain function.
- Scientific Name: Bacopa monnieri
- Additional Common Names: Water Hyssop, Brahmi, Herb of Grace, Creeping Jenny
- Origin: Wetlands Worldwide
- Height: 12 to 24 inches
- Light Requirements: Moderate to High
- Ease of Care: Easy
Caring for Moneywort in the Home Aquarium
Here are a few things you should consider when keeping Moneywort:
Lighting is one of the few areas where you might run into problems caring for Moneywort. It requires at least moderate light levels to do well and high light levels ensure it doesn’t drop its lower leaves even as it starts to hit the surface.
Exactly how much depends more on the type of fixtures you’re using. If you prefer fluorescent lighting you’ll need at a minimum 2-3 watts per gallon. However “watts per gallon” is not really the best way to measure lighting because it doesn’t take into account the surface area and depth of your aquarium.
Nor does it include PAR or photosynthetically active radiation. Or in layman’s terms: light that plants can actually make use of. LED plant lights provide the most PAR while using less power and outputting less heat than traditional fluorescent and incandescent fixtures.
Carbon Dioxide and Fertilizers
Like nearly all aquarium plants Moneywort will certainly thrive and show improved growth if given supplemental CO2. However one of the perks of this species is that it’s not required for healthy growth. Moneywort will grow somewhat more sluggish but will still tend to creep up until it covers the surface of the tank.
A rich substrate, on the other hand, is much more essential. Combined with moderate to high lighting Moneywort will put on rapid growth and remain an intensely lime green in color. If you’re designing a planted aquascape I suggest using a substrate designed to absorb and retain nutrients.
I discuss plant substrates in much greater detail in my review of planted aquarium substrates. But to save you some reading, I recommend giving Seachem Flourite a try.
Combine your Seachem Flourite with occasional doses of liquid fertilizer, of which there are plenty of great choices available. Since Fluorite has a high Cation Exchange Capacity (CEC) it will hold onto those liquid nutrients until the roots can uptake them properly.
Considering it grows on nearly every continent save Antarctica it should be no surprise that Moneywort tolerates a wide range of water conditions. However for best growth you’ll want to aim for a fairly moderate, tropical range. Temperatures should fall between 72-82F and pH should remain between 6.5-7.5 with moderate to low KH (Carbonate Hardness).
Aquascaping with Moneywort
Given its height, Moneywort is typically a mid to background plant. And being so hardy and quick to grow it’s an excellent first addition to any planted aquascape. Once it reaches the surface it will either grow laterally or simply push straight through the surface.
Healthy stems will send white roots out along leaf nodule points, making propagation a very straightforward process. Using sharp, clean scissors, simply cut the stem an inch below where the roots appear. Press the cutting into the aquarium substrate, using weights if necessary to keep them from floating away. Eventually the roots will extend down, anchoring the cutting in place.
Moneywort’s mostly vertical growth makes it easy to find a place in most aquascapes. But remember that it will grow laterally once it reaches the water’s surface, which can cause it to shade other aquarium plants.
It can even be left to float freely on the water’s surface. This is typically done in outdoor ponds and Nature Style Aquascapes. However floating Moneywort not only flowers but provides a dense habitat for fish fry, insect larvae, and surface dwelling fish.
I recommend Moneywort if you have an aquarium that has better lighting and a more nutrient rich substrate than most but you don’t want to fiddle with CO2 and want the plant to take off once rooted. Other than occasional trimming and dosing with fertilizer Moneywort is an attractive, low maintenance addition to any aquarium!