What is the Best Temperature for Aquarium Plants?
Aquatic plants require a variety of parameters to thrive in your aquarium. These include lighting, nutrients, the proper substrate, temperature, and several others.
Today, we will focus on temperature to assess your plant’s needs and figure out the ideal parameters to consider.
Does Temperature Matter for Aquarium Plants?
Yes, temperature is critical when it comes to accommodating your plants into their new environment. It also plays a major role moving forward, boosting the plant’s growth and improving its physiological processes.
What Temperature is Best for Aquarium Plants?
The ideal temperature range for most aquarium plants is 72-82 °F. These values are considered optimal for most tropical fish as well. This allows you to mix plants and fish with great success in terms of temperature compatibility.
That being said, most aquarium plants can withstand a wider temperature range. It depends on the plant’s development stage, species, and other aspects like available nutrients and water clarity. Here are some examples in this sense:
| Plant species | Temperature requirements |
| Guppy grass | 50-86 °F – This is an adaptable species, perfect for preserving the water chemistry and combating ammonia, nitrites, and heavy metals. |
| Water butterfly moss | 54-86 °F – This is a floating species that typically doesn’t require a heater. It’s hardy and adaptable and will grow fast when provided with adequate fertilization. |
| Floating Crystalwort | 56-86 °F – Another floating plant that’s easy to keep and that can thrive in most aquarium conditions. It will make a fine addition to heavily decorated environments, since the Crystalwort will attach to all surfaces available. |
| Java Moss | 58-86 °F – Java Moss needs no introduction. This species is great for breeding tanks, providing the eggs and fry with extra protection. Java moss requires more lighting than other species which can increase the risk of algae overgrowth. |
| Hornwort | 59-86 °F – Hornwort can grow up to 10 feet and is relatively easy to care for, making it great for inexperienced aquarists. Beware when adding this plant to an already planted aquarium. Hornwort is quite effective at consuming water nutrients, potentially starving other plants. |
| Brazilian Micro Sword | 59-83 °F – This is among the most popular carpet plants available. The micro sword has short stems but rich leaves, creating a lush substrate carpet for a more natural look. |
| Dwarf Baby Tears | 55-82 °F – Another carpet plant that’s great for breeding tanks. This species is more difficult to care for initially, but it becomes manageable once established in its environment. |
| Water Wisteria | 60-82 °F – Water wisteria is a floating plant that ranks among the most popular options for beginner and experienced aquarists. It’s easy to keep, but requires regular trimming to prevent it from cutting other plants’ access to light. |
| Amazon sword | 59-82 °F – Few things are as recognizable as the Amazon sword’s long and sharp leaves. This rooted plant is great for promoting a natural-looking environment and providing fish with hiding and resting areas. |
| African water fern | 58-84 °F – This one is a slow grower, so, you need to be patient. Otherwise, the African fern is easy to maintain, although it may be more demanding when still new to the tank. |
There are, naturally, a variety of other plants to consider, depending on your tank’s temperature setting, as well as other parameters. Since we’re here, I believe it’s time for a disclaimer. Researching the temperature requirements for the plants in this table will provide you with different values than what you’re seeing here.
In other words, the minimum temperatures will always be higher, typically above 70 °F. The reason why the minimum temperatures in my table are in the upper 50s is that that’s the lowest the plant can withstand. Most aquarium plants will begin to die soon bellow those values.
And even with these values, aquatic plants can only withstand temperatures bellow 60 °F for a short period. You should always look to keep your tank’s temperature in the lower or upper 70.
Do Aquarium Plants Freeze?
Yes, aquarium plants can freeze under the right circumstances. However, those are unlikely to occur. It would be difficult to imagine a circumstance where your tank’s temperature would drop so much that your plants freeze up.
Generally speaking, your tank’s temperature will never drop to the point where your plants risk freezing. So, them freezing isn’t something to be concerned about. What should concern you is the prolonged exposure to excessively low temperatures which will hurt the plants.
How Cold is Too Cold for Aquarium Plants?
There isn’t an overarching answer to this question. Different plants require different temperature ranges and what qualifies as too cold for one species may qualify as acceptable or preferable for another. For instance, plants like tiger lotus, dwarf lily, scarlet template, or water hibiscus do well in colder waters.
These plants will thrive in temperatures around 60 or even 55 °F. These temperatures are unacceptable for warm water plants like anubias, dwarf lotus, hygrophila, or java fern. You need temperatures in the mid-to-upper 70s for these species to thrive.
So, it all comes down to which plants we’re talking about.
Can Aquarium Plants Grow in Cold Water?
Yes, aquarium plants can grow in cold water, so long as those water parameters fit the plant’s profile. You can’t have warm water plants in cold water, since this such an environment will inhibit the plant’s growth rate significantly.
Do Aquarium Plants Grow Faster in Warm Water?
Overall, yes, aquatic plants grow faster the warmer the water is. But there’s a catch. There are, actually, several catches. Here are some things to ponder upon:
- There is a limit – Naturally, plants will enjoy higher temperatures up to a point. Beyond that point, the excessive warmth will work against the plant, causing it to die.
- The need for more nutrients – The warmer water will accelerate the plant’s metabolic rates. In other words, the plant will consume more nutrients, including CO2. If not enough nutrients are available in the environment, the higher temperatures will actually do the plant a disservice.
- Warmer isn’t always better – While I understand the appeal of having faster-growing plants, the problem is not all plants react the same to higher temperatures. Some may even have problems and experience hindered growth when the temperatures rise. So, it all comes down to your plant’s preferences.
Colder waters are often better than warmer ones – In essence, you should figure out the goldilocks zone in terms of water temperature. Plants will generally appreciate slightly colder waters, compared to warmer ones. That’s because colder waters offer the ideal balance between plant growth and nutrient consumption. How cold the water should be ideally depends on the plant itself.
So, yes, plants will grow faster in warmer waters. But, as you can see, the situation is not all black and white. There are layers to consider.
Conclusion
Aquatic plants demand varying temperatures based on each species’ requirements. For the most part, aquatic plants in thrive in temperatures between 70 and 75 F. But they will also do just fine at values around 80 °F or slightly higher. The idea is to figure out your favorite plant’s temperature requirements before purchasing it.
This way, you can adjust your expectations and craft a better and more stable aquatic environment as a result.
