Cold water aquariums are a fantastic option for fishkeepers looking for an alternative to the more common tropical setups. While tropical aquariums require heaters and more involved maintenance routines, cold water tanks are simpler and lower cost. Many beautiful fish thrive in cooler temperatures, including favorites like goldfish, white cloud mountain minnows, and weather loaches.
In addition to fish, a key component of any aquarium environment is the plants. Choosing suitable plant life is crucial for replicating natural ecosystems and supporting fish health. Plants help filter the water, provide shelter, regulate pH levels, and introduce visual interest.
What is a Cold Water Aquarium?
Before diving into plant specifics, let’s ensure we’re on the same page regarding what defines a cold water aquarium.
Cold water tanks are aquariums housed at room temperature without artificial heating. This means the water temperature typically ranges between 60-72°F (15-22°C). They do not require special heaters or chillers to maintain cooler temperatures.
These conditions are ideal for fish species originating from temperate climate zones rather than tropical environments. Common inhabitants include:
- Goldfish
- White cloud mountain minnows
- Weather/dojo loaches
- Rosy barbs
- Rainbow shiners
- Paradise fish
- Zebra danios
- Hillstream loaches
While tropical fish require warm water in the 70-82°F (21-28°C) range, these cold water natives are more comfortable at lower temps closer to their natural ecosystems. Keeping them in cooler aquariums avoids unnecessary stress on their metabolism and immune systems.
Now that we know what defines a cold water habitat, let’s examine why aquarium plants are so beneficial.
Benefits of Aquarium Plants
There are many advantages to incorporating live plants into cold water aquarium setups. Here are some of the top reasons to go green:
Improved Water Quality
One of the biggest benefits is that plants act as natural filters to keep water cleaner and parameters more stable. Aquatic plants absorb dissolved wastes like ammonia, nitrites, and nitrates through their tissue and root systems. This helps prevent the buildup of toxic compounds from fish waste, leftover food, and other organic matter. Plants make excellent chemical sponges to remove pollutants.
They also oxygenate the water through photosynthesis. This added oxygen is essential for fish respiration and healthy gill function.
Natural Habitats & Enrichment
Aquarium plants let you recreate naturalistic biotopes and provide environmental enrichment for fish. Species like tetra and rasboras flock to thickets of plants in the wild for shelter and security.
Planted aquariums offer a comfortable, stimulating habitat. Fish exhibit more natural behaviors and are less stressed than sparse, artificial decor. Vibrant live plants bring an authentic slice of nature into your home.
Visual Interest
Let’s not overlook aesthetics! Aquatic plants look stunning, lending color, texture, scale, and dimension to aquascape designs. You can create breathtaking mixed-green layouts or choose species with purple, red, pink, orange and other vibrant foliage. Cold water setups may be lower maintenance, but they can still have jaw-dropping beauty with the right plants.
Healthier Fish
All these benefits directly contribute to healthier fish with stronger immune systems and more active lifestyles. Plants improve water parameters and oxygenation while reducing environmental stress. Your fish will exhibit brighter coloration and live their best in a well-planted habitat.
Best Cold Water Aquarium Plants
Now that we’ve covered the merits of adding plants, let’s get into the fun part – choosing species!
With thousands of aquatic plant varieties out there, it can get overwhelming. To help narrow your options, here are 15 of the top choices for unheated cold water tanks:
Anacharis
Water Temperature Range: 50-82°F
Anacharis is a classic, easy stem plant for beginners. Its long green stems grow up to 10 inches per week, so it’s great for soaking up excess nutrients. Trim regularly to keep it compact. Anacharis thrives in a wide temperature span from 50-82°F, making it suitable for cold water setups.
Java Fern
Water Temperature Range: 60-85°F
The hardy Java fern adapts to many conditions, including cold aquariums. It has broad, deep green leaves that provide shelter and surface area for beneficial bacteria. Java fern propagates through plantlets on the leaf margins, allowing it to spread over time.
Java Moss
Water Temperature Range: 59-86°F
Java moss is a versatile foreground plant. Its fine filaments anchor readily to rocks, wood, and decor. This moss grows in lush green carpets and tolerates a wide temperature range. It’s undemanding, thriving without special substrate or fertilization.
Hornwort
Water Temperature Range: 59-86°F
Hornwort is a cold water favorite, growing up to 12 inches tall in tufts. Its thin fronds provide dense cover. Hornwort controls algae through fast growth fueled by readily available nutrients like nitrates and phosphates.
Marimo Moss Balls
Water Temperature Range: 50-80°F
No algae-lover’s tank is complete without marimo moss balls! These spherical aquarium plants are a species of green algae (Aegagropila linnaei). They grow slowly, requiring minimal care while adding texture and interest.
Water Wisteria
Water Temperature Range: 64-82°F
Water wisteria is a fast-growing stem plant with attractive green leaves. It propagates through both its roots and stem cuttings. Water wisteria is undemanding, able to thrive in low-tech setups. It prefers at least 64°F but can survive cooler temps.
Cryptocoryne
Water Temperature Range: 66-84°F
Cryptocorynes are excellent midground plants with broad leaves. There are many color varieties, from green to red to purple. They grow slowly from rhizomes anchored in the substrate. Crypts thrive with added carbon dioxide and nutrients.
Rotala
Water Temperature Range: 65-82°F
Rotala are delicate stemmed plants great for background placement. You can find green varieties along with red-hued cultivars. Rotala becomes bushy with dense foliage when pruned frequently. It grows rapidly and benefits from added CO2.
Cabomba
Water Temperature Range: 64-86°F
With feathery green leaves, cabomba makes an attractive background plant. It can grow up to 3 inches per week under optimal conditions. While cabomba flourishes with high light and nutrients, it can tolerate a range of setups. Ideal water temperature is 70-82°F, but it survives down to 64°F.
Ludwigia
Water Temperature Range: 64-82°F
Ludwigia offers bright green foliage and vivid red coloring. There are many color varieties to give pops of color, like Ludwigia ‘Red.’ It appreciates moderate to high light. Ludwigia is a versatile stem plant suitable for mid-ground placement in cold water tanks.
Bacopa
Water Temperature Range: 64-82°F
The trailing stems of bacopa make it perfect for cascading layouts. Its small leaves come in green, gold, and red-brown hues. Bacopa is undemanding, thriving in low-tech cold water setups. It grows rapidly and benefits from frequent pruning.
Amazon Sword
Water Temperature Range: 62-82°F
Amazon swords are classic aquarium centerpiece plants, thriving in various water temperatures down to 62°F. Their lush green leaves grow up to 24 inches, making them excellent for background placement. These versatile community tank plants propagate via runners.
Java Fern ‘Windelov’
Water Temperature Range: 60-85°F
‘Windelov’ is a Java fern cultivar with delicate, lacy fronds. It has the same undemanding nature and broad temperature tolerance as standard Java fern. Windelov fern looks stunning grown on driftwood and rocks.
Water Sprite
Water Temperature Range: 60-85°F
Water sprite is a versatile floater. Its trailing stems form thick floating mats at the surface while the leaves reach downwards like immersed growth. It is fast-growing and helps control algae through rapid nutrient uptake.
Additional Cold Water Plant Options:
- Anubias (Anubias barteri var. nana)
- Pearl Weed (Hemianthus micranthemoides)
- Floating Hornwort (Ceratophyllum demersum)
- African Water Fern (Bolbitis heudelotii)
- Subwassertang (Süßwassertang)
- Guppy Grass (Najas guadalupensis)
- Fanwort (Cabomba caroliniana)
- Dwarf Sagittaria (Sagittaria subulata)
This covers a wide selection of suitable plants! Mix low-light beginner-friendly plants with advanced species to create your ideal cold water aquascape.
Advanced Cold Water Aquarium Plants
So far, the species we’ve covered are suitable for beginner to intermediate hobbyists. But those with more experience may want to add advanced plants to make their cold water tanks pop. Here are 5 impressive choices to take your aquascape to the next level:
Red Tiger Lotus
Water Temperature Range: 70-82°F
While tiger lotus prefers warmer temperatures around 70-82°F, you can successfully grow it in the upper range of cold water tanks. It offers vibrant red leaves that contrast beautifully with cool-toned fish species. Provide ample nutrients and light for the best coloring.
Dwarf Baby Tears
Water Temperature Range: 65-82°F
Dwarf baby tears form dense, lush carpets ideal for sophisticated aquascape foregrounds. Optimal growth occurs between 70-80°F, but they survive down to 65°F. Supplement with CO2 and excel in high-tech setups with ample nutrients and light.
Monte Carlo
Water Temperature Range: 65-85°F
The tiny rounded leaves of Monte Carlo create eye-catching emerald green carpets. While it grows best with CO2 supplementation, Monte Carlo can thrive in cold water tanks given sufficient lighting. Slow growth at lower temperatures results in compact growth.
Blyxa Japonica
Water Temperature Range: 68-86°F
Blyxa Japonica adds height and structure with its long blades. Provide moderate to high light to bring out its reddish tones. It prefers warmer water from 75-82°F but tolerates temps as low as 68°F. Add root tabs for iron to encourage red coloring.
Alternanthera Reineckii ‘Mini’
Water Temperature Range: 71-82°F
‘Mini’ Alternanthera develops rich rose-colored leaves under high light and CO2 injection. While it thrives between 75-82°F, you can grow it to around 71°F. Place in the mid or background for pops of color.
Unconventional Cold Water Species
Looking to stand out from the crowd? Try your hand at growing these unconventional aquatic plants suitable for cold water setups:
- Banana Plant (Nymphoides aquatica) – Unique banana-shaped leaves
- Madagascar Lace Plant (Aponogeton madagascariensis) – Delicate lace-patterned foliage
- Red Mangrove (Rhizophora mangle) – Striking red tidal plant that can grow emersed or submersed
- Ribbon Plant (Vallisneria americana) – Long grass-like leaves that sway gracefully
- Water Poppy (Hydrocleys nymphoides) – Lily pads with vibrant yellow flowers
- Parrot Feather (Myriophyllum aquaticum) – Feathery blue-green stems that reach the surface
- American Waterweed (Elodea canadensis) – Hardy, fast-growing oxygenator
- African Water Fern (Bolbitis heudelotii) – Broad green leaves reminiscent of terrestrial ferns
Don’t be afraid to experiment with exotic cold water plants to stand out. Just be sure to research their care requirements first!
Cold Water Plant Care Tips
Caring for plants in cold water aquariums only requires a few simple guidelines:
Lighting
Most cold water plants need low to moderate light levels, in the range of 1-2 watts per gallon provided by fluorescent or LED fixtures. Plants like anubias and Java fern do fine in low light. Stems like ludwigia and cabomba appreciate moderate to high intensity.
Use a timer to ensure consistent photoperiods of 8-10 hours daily. Avoid direct sunlight, which can cause excessive algae.
Substrate
Plant-friendly substrate supports healthy root growth. Choose fine gravel or sand, with a grain size of 1-3mm. Some specialized options are ADA Aquasoil, Eco-Complete, and Fluorite.
Depth should be 1-2 inches in the front sloping to 3-4 inches in the back. Use plant weights or tie plants to decor instead of deep substrate if needed.
Fertilization
While cold water plants are relatively undemanding, fertilization can support optimal growth. Use comprehensive liquid fertilizers or root tabs placed near rooted plants as directed on the packaging.
With fish stock, plants often get enough nutrients through waste. But you may need to supplement in sparsely stocked tanks.
CO2 Injection
Adding carbon dioxide allows plants to photosynthesize faster. But it’s not essential in most low-tech cold water setups. Save CO2 systems for tanks with more advanced plants like glossostigma that need elevated levels.
Maintenance
Prune stem plants as they outgrow their space to encourage bushy, compact growth. Remove dying leaves and debris during partial water changes. Wipe algae from leaves. Replenish root tabs every 3-4 months per the package directions.
Designing Your Cold Water Aquascape
Aquascaping is the artful process of arranging hardscape and plants into an underwater landscape. Follow these tips to design your perfect cold water planted tank:
Choose Suitable Plants
Select plants suited to your setup’s conditions – like water temperature, lighting, nutrients, and available space. Group plants with similar needs together.
Plan Hardscape
Hardscape provides structure and scale before adding plants. Use driftwood, rocks, and other decor to create height levels and dimension.
Foreground, Midground, Background
Place low-growing plants up front, medium height in the middle, and tall stem plants in the back. This creates depth and layers.
Utilize Triangles
Arrange plants in uneven numbers of triangular groupings rather than rigid rows for a natural look.
Transitions
Transition from fine-leaved plants to broader leaves as you move from foreground to background.
Direct the Eye
Use large focal point plants to draw the eye and guide the viewer through the layout.
Follow aquascaping composition basics to design a balanced, aesthetically pleasing planted tank. Then sit back and enjoy watching your cold water garden flourish!
Cold Water Aquarium Plants FAQ
Let’s wrap up with answers to some frequently asked questions about keeping plants in cold water setups:
What plants work in unheated goldfish tanks?
Anacharis, hornwort, Java fern and moss, marimo moss balls, and Amazon sword are excellent for goldfish aquariums. These species tolerate nipping and the messy environment goldfish create.
Do I need special aquarium plant substrate for cold water tanks?
While specialized plant substrates like Fluorite can be beneficial, they are not essential. Plain gravel or sand works fine if you fertilize rooted plants with root tabs or liquid ferts.
Should I add CO2 to my cold water planted tank?
Most low-tech cold water setups grow plants just fine without added carbon dioxide. Save CO2 systems for planted tanks with more advanced species requiring increased carbon for faster growth.
Can I grow aquatic carpet plants in cold water aquariums?
Several carpeting species like Marsilea hirsuta and Monte Carlo tolerate lower temperatures down to the mid 60s F. But they often grow slower than in heated setups. Stick to Java moss or dwarf sag for easier carpeting options.
How do I control algae in cold water planted tanks?
Promote fast-growing stems, don’t overstock with fish, provide consistent lighting periods, manually remove algae buildup, and perform regular water changes to prevent excessive algae growth.
Troubleshooting Common Cold Water Plant Problems
Even seasoned aquarists run into plant problems now and then. Here are some common cold water plant pitfalls and how to address them:
Problem: Stunted, yellowing growth
Cause: Nutrient deficiency
Solution: Fertilize regularly with a comprehensive liquid or root tabs
Problem: Algae growth on leaves
Cause: Excess light, organics, or nutrients
Solution: Reduce lighting duration, clean tank, do more frequent water changes
Problem: Leaves turning transparent and melting
Cause: Lack of nutrients or planted too deeply
Solution: Move to proper depth, ensure quality substrate and fertilization
Problem: Holes in leaves, chewed stems
Cause: Fish nibbling on plants
Solution: Add algae-grazing fish like otocinclus to divert attention
Problem: Plants becoming loose and uprooting
Cause: Improper planting or lack of strong roots
Solution: Replant securely with tweezers and use weights until established
Don’t hesitate to ask experienced aquarists for help if your plants are struggling. Most issues can be remedied with some adjustments.
Final Thoughts
We’ve covered everything from suitable plant species to design techniques for thriving cold water planted aquariums. Understanding plant needs, providing adequate lighting and nutrients, and following composition principles can create a stunning aquatic garden.
Cold water setups present a rewarding challenge. Take it step by step – mastering the basics before working up to advanced aquascaping. Half the fun is in the process. Don’t be afraid to experiment and make changes until your tank reaches its full potential.
Soon you’ll have a flourishing underwater oasis with happier, healthier fish thanks to the benefits of live plants. Your cold water aquarium will become a peaceful focal point full of life.
If you have any other questions as you embark on your planted tank journey, don’t hesitate to ask. We wish you the best of luck and inspiration as you cultivate your perfect cold water aquascape. Let your creativity flow!
