🌿 Plants not growing in freshwater aquariums – causes, solutions and tips for healthy growth

🌱 When nothing grows in the aquarium anymore…

Lush green aquatic plants are not only beautiful to look at – they are also a crucial part of the biological balance. They produce oxygen, deprive algae of nutrients, and provide hiding places for fish and invertebrates. 🌿
But sometimes they just won't grow or even die after a short time. 🤔

The good news: In most cases, the problem is not with the plant itself, but with a few basic conditions that can easily be optimized.

🔍 Common causes of poor plant growth

☀️ Too little or wrong light

Plants need light to photosynthesize. Without sufficient light, they stagnate or die.

  • Light duration: 6–8 hours daily

  • Light color: approx. 6,500 K (daylight spectrum)

🧪 Nutrient deficiency

Plants cannot grow if they lack essential macro- or micronutrients. Typical deficiency symptoms include:

  • Yellow leaves → Iron deficiency

  • Holes or glassiness → Potassium deficiency

  • Weak growth → too little nitrate or phosphate

💨 No or too little CO₂

Carbon dioxide is the most important plant nutrient. Without CO₂, many species grow slowly or not at all. Particularly fast-growing stem plants require more CO₂ than slow-growing species.

🪵 Unfavorable water quality

Too high a pH value, water that is too hard, or strong fluctuations can inhibit growth.

  • pH: 6.5 – 7.5

  • KH: 4 – 8 °dKH

  • GH: 6 – 14 °dGH

🪸 Competition from algae

Excessive algae growth can "suffocate" plants, as algae deprive them of light and nutrients.

✅ Step-by-step: How to make your plants grow strong again

☀️ 1. Check lighting conditions

  • Light your aquarium for 6-8 hours daily.

  • Make sure you use a neutral light spectrum (approx. 6,500 K).

  • Clean the covers and lights regularly.

🧪 2. Ensure a balanced supply of nutrients

Plants need macronutrients (nitrate, phosphate, potassium) and micronutrients (iron, trace elements) .

  • Use liquid fertilizer regularly.

  • Fertilize according to water analysis and plant needs.

👉 In our shop you will find high-quality plant fertilizers and nutrient preparations that optimally supply your plants.

💨 3. Optimize CO₂ supply

Even if you don't use a CO₂ system, you can reduce the CO₂ level through surface agitation or by supplementing with natural CO₂ sources. For heavily planted aquariums, CO₂ supplementation is almost always beneficial.

🪸 4. Check water parameters

Stable water parameters are crucial for healthy plant growth. Regularly test pH, KH, and GH to ensure your plants can optimally absorb nutrients.

🧹 5. Control algae growth

  • Reduce light duration and nutrients if there is heavy algae growth.

  • Use fast-growing plants to compete with algae.

  • Invertebrates such as snails or shrimp help to reduce algae and biofilms.

👉 In our shop you will find useful invertebrates that will keep your aquarium clean and help your plants get off to a good start.

🌿 Plants for beginners – our tips

If you are having problems with growth, start with robust, fast-growing varieties such as:

  • Waterweed ( Elodea densa )

  • Hornwort ( Ceratophyllum demersum )

  • Hygrophila polysperma

  • Vallisneria spiralis

These plants are forgiving of minor mistakes and help to keep your aquarium stable.

🧠 Prevention – so your plants stay healthy in the long term

  • 💡 Sufficient light and correct lighting duration

  • 💧 Regular nutrient supply and CO₂ intake

  • 📊 Monitor and maintain stable water parameters

  • 🌿 Use fast-growing plants

  • 🐌 Integrate beneficial invertebrates

✅ Conclusion: Healthy plants are the key to success

Poor plant growth is almost always a sign of an imbalance – too little light, nutrients, or CO₂. Optimizing these factors will help your plants grow strong again, look healthy, and contribute significantly to the stability of your aquarium. 🌿

👉 Discover high-quality plant fertilizers, nutrient additives and beneficial invertebrates in our shop now, which will give your plants a boost.

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