Ah, the eternal question: should you add CO₂ or not? I remember my first tank becoming completely overgrown with algae. Why? I had strong lighting, but no CO₂. The result: drooping plants and thriving algae. Still, a CO₂ system isn't for everyone – it costs money, maintenance, and requires a bit of skill. Fortunately, there are also plants that can thrive without CO₂. And low-tech can secretly be wonderfully relaxing. In this blog post, I'll explain the differences and which option is right for you.
High-tech aquariums with CO₂ promote faster growth, red plants, and carpet plants. Low-tech aquariums without CO₂ are cheaper, easier, and ideal for beginners. The choice depends on your plants, your budget, and the amount of maintenance you want to do.
What is the difference between low tech and high tech?
High-tech means: CO₂ injection. You use a cylinder, a regulator, and a diffuser to inject extra CO₂ into the water. This makes your plants grow much faster (sometimes 5–10 times faster), they stay more compact, and red varieties truly develop their color. Carpet plants like Hemianthus callitrichoides or reddish-colored plants like Rotala only thrive with extra CO₂. It also helps prevent algae growth, because your plants simply consume all the nutrients faster.
Low-tech grows, on the other hand, simply run on the natural amount of CO₂ dissolved in the water. This is often combined with moderate light and robust plants like Anubias, Cryptocoryne, and Java fern. You can add some liquid carbon (such as EasyCarbo), but this is no substitute for actual CO₂ injection. Low-tech grows slower, but that's sometimes a good thing: less pruning, less hassle, and still a beautiful green container.
When do you choose a high-tech or low-tech aquarium?
- Decide on your plant preferences: red stems or a dense carpet → go high-tech; easy plants → low-tech is fine.
- Check your budget: a CO₂ kit (cylinder, regulator, diffuser, drop checker) is expensive; low-tech is cheaper.
- For high-tech grows: set your regulator correctly, start at around 20–30 ppm CO₂, and let the drop checker turn a nice green. Gradually increase the light and nutrients.
- For low-tech grows: choose shade-loving plants, keep the lighting moderate, and fertilize as needed. Add liquid carbon if needed—but be careful with sensitive plants like Vallisneria, which don't tolerate it well.
- Maintenance: High-tech involves more frequent pruning, water changes, and checking your CO₂ system; low-tech allows for a much more relaxed approach.
Common mistakes (and quick fixes)
- Bright light without CO₂: guaranteed algae growth. Fix: lower the light or add CO₂.
- CO₂ but no nutrients: plants suffer from deficiencies. Fix: add macro- and micronutrients.
- Poor installation: leaky hoses or unstable pH. Fix: Check your system and replace the rubber seals in time.
Checklist
- Do you want easy plants or difficult varieties?
- What is your budget for a CO₂ set?
- How much time do you have for maintenance?
- Do you have a high-tech drop checker?
- Are you using food (liquid or root tabs)?
Conclusion
CO₂ isn't essential, but it can boost your aquarium's performance. Low-tech is relaxing, less expensive, and perfect for beginners. High-tech delivers spectacular results but requires more attention. Still unsure? Feel free to send us a message; we'd be happy to help you get your tank in top shape.
Read more: Red aquarium plants , Successfully keeping aquarium plants .
