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Red aquarium plants, how and why? Unravelling the Mystery.

Red-coloured aquarium plants hold a special allure within the planted aquarium community. While not all plants possess the genetic trait to turn red, there are several species that can display vibrant red hues under the right conditions. In this article, we will explore the key factors that contribute to the development of deep red coloration in aquarium plants, as well as provide suitable options for beginners in the realm of planted tanks. It is important to note that the provision of optimal conditions, such as high-tech setups with CO2 supplementation, intense lighting, and fertilizers, tends to promote overall plant health and potentially enhance red coloration.

The Role of Carbon Dioxide (CO2): Carbon dioxide is a critical element in the growth, development, and appearance of all aquatic plants. Many plants, initially appearing green, can transition to exhibit red accents or even turn entirely red when supplied with sufficient levels of CO2. For most planted tank enthusiasts, maintaining CO2 levels between 20-40 ppm proves to be ideal. The goal is to achieve a CO2 saturation point that fulfills the plants' requirements without exceeding the necessary amount. Excessive CO2 can lead to fish distress, causing them to gasp for air and potentially resulting in fatalities. Fortunately, plants themselves can tolerate elevated CO2 levels without adverse effects.

The Significance of Light Intensity: Although CO2 plays a vital role in determining red coloration, it is not the sole determining factor. Light intensity also significantly influences plant coloration, and it is often the primary consideration for aquarists when assessing the redness of their plants. Notably, when certain plants reach closer to the water's surface, where light intensity is higher, the tips tend to turn red while the rest of the plant remains green. This observation suggests that the proximity, strength, and wavelength of the light source contribute to the manifestation of red coloration. In our summer submerged containers, the benefit of intense light is highlighted with intense reds on all plants that can produce red leaves even though we do not add fertilizers or CO2 leading me to believe lighting is the most important aspect.

Studies suggest that the intensified red pigment serves as a form of sunscreen for the plant cells. Therefore, increasing light intensity can result in visible "suntanning" of certain plants, enhancing their red coloration. I whole heartedly support this! The PROOF is this Bacopa amplexicaulis that normally stay green BUT turned a purple / red colour in our submerged tubs!! AWASOME

Iron (Fe) and its Role: Iron (Fe) is an essential micronutrient for all aquarium plants, found in various cellular components. It serves as a co-factor in many enzymes involved in pigment generation and, consequently, the expression of red coloration in plants. Some hobbyists emphasize the supplementation of iron as a key factor in achieving red plants. While this viewpoint is not entirely inaccurate, as iron does play a role, it is worth noting that plants can readily exhibit red coloration without additional iron supplementation. This does not imply a lack of iron availability; rather, it emphasizes the pivotal influence of CO2 and lighting, which yield the most pronounced shifts in plant coloration. While iron plays a vital role in the production of red pigments in plants, it is important to note that dosing extra iron beyond trace amounts does not lead to an increase in red pigment or pigment intensity. The plants will not produce more red pigment than necessary just because additional iron is provided. A little iron goes a long way, and overdosing on iron can be harmful to sensitive invertebrates like shrimp, which are highly sensitive to free copper and iron cations. Thus, it is crucial to maintain a balanced approach to iron supplementation to avoid adverse effects. In some cases, adding laterite clay to the substrate or incorporating liquid fertilizers containing small amounts of iron can enhance iron availability to the plants through the roots. However, it is important to highlight that the most remarkable changes in plant coloration consistently stem from the interplay of CO2 and lighting.

Nitrate Levels: Surprisingly, lowering nitrates may also play a role in achieving peak redness in aquarium plants. Initially met with skepticism, this concept aligns with observations shared within the aquascaping community. While further research is needed to fully understand the mechanisms involved, it appears that reducing nitrates in the aquarium environment may positively impactthe intensity of red coloration in plants. Experimentation and observation remain essential in determining the optimal nitrate levels for promoting vibrant red hues in aquarium plants.

To unlock the full potential of red coloration in aquarium plants, bright light and ample CO2 injection are key factors. While some plants, such as Ludwigia super red, can exhibit vibrant red hues even under moderate lighting conditions, most rotalas and other red plants require intense lighting in the appropriate spectrum/wavelength to achieve their full-color potential. In fact, studies suggest that the intensified red pigment serves as a form of sunscreen for the plant cells. Therefore, increasing light intensity can result in visible "suntanning" of certain plants, enhancing their red coloration. In conclusion, achieving red coloration in aquarium plants is a captivating pursuit for many enthusiasts. By prioritizing the provision of appropriate CO2 levels, optimizing lighting intensity, and ensuring sufficient iron availability, aquarists can enhance the likelihood of vibrant red hues in their planted tanks. However, it is important to remember that each plant species may respond differently to these factors, and experimentation and observation remain crucial to unlocking the true potential of red coloration in the aquatic plant world. Visit our online store for the largest selection of aquarium plants ++ Pond & Terrarium plants galore

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