I think it’s important to understand how plants grow to be successful. So here is a little bit of what I learned. Aquatic plants grow in water and the surrounding water provides support for aquatic plants, most stems of aquatic plants are thinner and more flexible. Those flexible stems allow plants to move with the water flow and preventing them from breaking. Terrestrial plant leaves have a thick waxy outer layer and it prevent leaves from drying out, in aquatic plants leaves that part is thinner and water is able to pass thru much easily which help plants to get nutrients. Some aquatic plants do grow above the water surface and produce two different leave shapes below and above water. But like terrestrial plant aquatic plant leaves collect sunlight and carry out photosynthesis, stems provide support and transfer gases, water, and nutrients. Roots branch out to anchor the plant. Some aquatic plants grow in clumps or rosettes of leaves; some grow from bulbs which contain large reserve of nutrients. Terrestrial plant have roots that resemble fine hairs and its those are not present in most plants that grow under water, some of those hair like roots may develop in some bog plants when grown out of water. Large plants grow long roots for good anchorage and wide nutrient collecting area. Plants that grow in shallow water are smaller and have shorter, thinner roots. In nature the substrate where they grow is often shallow with little water movement so they do not need long roots for anchorage. Some plants are adapted to live above the substrate and will attach themselves to rock or wood. There is also floating plants that do not need anchorage and they have fine branched roots. Some plants like Anubias grow roots from rhizome, they can be grown attached to wood or rock or in substrate but do not burry the rhizome. Most of the aquatic plants produce seeds and flowers above the water so that they can be pollinated by insects. Some produce flowers under water and a few do not produce flowers at all.
Plants absorb important elements directly from their surrounding environment and that’s why plants were able to spread into many habitats. Plants have a little control over the rate of photosynthesis that occurs within its cells and several environmental aspects play an important role. Light is the most obvious component also temperature, CO2 (carbon dioxide) levels, all affect the rate of photosynthesis. Plants obtain their energy from sunlight, CO2 and water using the process of photosynthesis. Photosynthesis occurs during the day and unlike photosynthesis respiration is a continual process that doesn’t stop at night. Photosynthesis stores food (energy), respiration releases energy. In 24 hours plant release more oxygen through photosynthesis than they use during respiration. Many fast growing plants sold as oxygenating plant for that reason. Fish and bacteria also use up oxygen continually through respiration; actually bacteria are the biggest consumers of oxygen in aquarium.