5 Best Aquarium Plants for High Tech Planted Tanks with CO2

Have you ever heard the words “low tech” and “high tech” being used when referring to a planted aquarium and wondered what the difference was? To put it simply, the more energy that goes into an aquarium setup, the “higher tech” it is. A high tech planted tank may use intensely bright lighting, a pressurized carbon dioxide (CO₂) gas system, and large amounts of fertilizer. Because a lot of energy is going into the system, high tech setups are often very costly and need more maintenance than a low tech tank. A low tech planted tank may use low lighting, no additional CO₂, and minimal fertilizing once per week. In turn, low light setups are usually less expensive and easier to maintain in the long term.

With the exception of a few species, almost any aquarium plant has the ability to thrive in a high tech tank because all of its needs (e.g., nutrients, light, and CO₂) are being met in abundance. However, there are many plants in the aquarium trade that will only survive under those conditions. The plants discussed in this article have been carefully selected because they can grow in both low tech and high tech environments. However, what you might not know is that the same plant growing in a low tech aquarium can look entirely different or even become a different color when grown in a high tech aquarium.

1. Scarlet Temple

Alternanthera reineckii (also known as scarlet temple or “AR”) is a naturally pink-colored plant even in an aquarium without bright lights and added CO₂. The undersides of the leaves will remain vibrant pink while the surface of the leaves appear more golden brown. However, when growing this plant with medium to high light and added nutrients (especially CO₂), it is possible to achieve deep red to pinkish-red, magenta coloration throughout the entire plant. 

Scarlet temple or Alternanthera reineckii

2. Hydrocotyle tripartita ‘Japan’

What makes Hydrocotyle tripartita ‘Japan’ unique is that the leaves appear just like miniature shamrock or clover leaves. It is a small and delicate plant, which makes it perfect for aquascaping. In a low tech tank, this plant may grow long stems in a slightly upward growth pattern or may creep along the surface of the substrate loosely. However, when given a high tech environment and regular pruning, this plant can become quite dense, bushy, and low-growing with many leaves, forming a lush pillow of clovers.

Hydrocotyle tripartita ‘Japan’

3. Dwarf Baby Tears

While certainly not impossible, it can be difficult for many to achieve a thick, dense carpet of dwarf baby tears (Hemianthus callitrichoides ‘Cuba’) without high light and pressurized CO₂. On the other hand, it can be successfully grown to its fullest potential in a “lower tech” tank if given at least medium light, plenty of nutrients, and enough time – with the last part being the most important. Those who do not want to wait many months for a mature carpet to form can opt to add this plant to a high tech tank where it will grow at a much, much faster rate. Dwarf baby tears is a unique plant with some of the tiniest leaves of any aquatic plant in the trade, and it is truly enjoyable to watch it grow and fill in.

Dwarf baby tears or Hemianthus callitrichoides ‘Cuba’

4. Monte Carlo

Micranthemum tweediei or Micranthemum ‘Monte Carlo’ is an excellent alternative to those with little luck growing the aforementioned dwarf baby tears. This plant doesn’t require quite as much care and grows at a slightly faster rate, even in a low tech environment. However, if you give it at least medium light and plenty of essential nutrients, monte carlo can really take off and form a cascading river of green leaves along the substrate of your tank.

Monte carlo or Micranthemum tweediei

5. Ammannia gracilis

Ammannia gracilis is quite a beautiful plant. Like the colors of our ever-changing autumn leaves, this stem plant can take on various shades of yellow, orange, and red, depending on the conditions in which it is growing. A low tech tank with medium lighting will bring out a greenish-yellow to light orange color in Ammannia gracilis specimens. On the other hand, a high tech tank with high lighting, CO₂, and a lot of nutrients will allow this plant to color up to its fullest potential and exhibit bright red to an almost maroon-pink color throughout the entire plant.

Ammannia gracilis

Bonus: Christmas Moss

You may not have expected this curveball, but Christmas moss or Vesicularia montagnei is a moss that can do quite well in a high tech environment under high light conditions. With a lot of light, extra CO₂, and a hefty fertilizer dosing schedule, a more compact growth pattern can be observed. As the moss grows, the fronds or new “leaves” remain closer together, tightly layered, and more horizontal in a high tech tank. In a low tech setup, the growth pattern is slightly less compact and more vertical in position as the new fronds reach to absorb as much light as possible.

Christmas moss or Vesicularia montagnei

Why Do Plants Turn Red in a High Tech Aquarium?

The simplest answer is light and an important pigment called anthocyanin – the same chemical that gives us red leaves in the fall and some vegetables and fruits their red or purple color. A green plant contains a pigment called chlorophyll, which makes it appear green to our eyes. However, chlorophyll can be easily damaged by intense levels of light. To fight this, the plant produces a different red pigment called anthocyanin. This pigment is more capable of withstanding extremely bright lighting and can actually absorb the excess light energy in a way that is not harmful to the plant. Essentially, anthocyanins or the red color we see is acting as a “sunscreen” to shield the plant cells from being burned.

For recommendations on which lighting to get for a high light versus low light tank, check out our LED Aquarium Lighting Guide.