| Although its possible to keep fish in a bare aquarium, | | | | canadensis or Candian Pondweed which will do well |
| most people like to provide their fish with a more | | | | enough if rooted in gravel or sand alone with nothing |
| natural looking-environment. A planted aquarium not | | | | more than mulm as a sole nutrient source, but will do |
| only looks good but the plants also help to aerate the | | | | much better if given regular doses of plant fertilizer |
| water by giving off oxygen from their submerged | | | | applied sparingly. |
| leaves. Many, if not most, rooted aquatic plants take | | | | Certain plants, such as the bog dwelling Amazon |
| in nutrients through their leaves but will not thrive | | | | Sword and the Crypts, thrive best if given a wider |
| unless they can take in additional nourishment through | | | | range of nutrients. Mixing a planting medium such |
| their roots. The choice of a bedding or rooting | | | | Tetra Complete Substrate or Laterite with gravel will |
| medium is therefore an important one for the keen | | | | ensure that plants with a richer nutrient requirement |
| aquarist. | | | | will remain healthy. Liquid plant food or tablets can be |
| Aquarium gravel is by far the most commonly used | | | | added periodically if required in addition to the planting |
| bed material and does not contaminate the water if | | | | medium. Another way of catering for bog plants that |
| washed before use. Gravel with a grain size of 3mm | | | | grow best in more than just gravel is to buy them |
| to 6mm is a good choice for most uses. Sand is also | | | | potted in their own peat, loam or bulb fibre with a |
| a popular substrate for planted aquaria and tends to | | | | topping of gravel. This way, the special rooting |
| hold rooted plants more firmly. If used in a layer | | | | medium is confined and you have the choice of |
| more than 2cm deep anaerobic decay of organic | | | | moving the plants around without disturbing the root |
| matter will occur in pockets were not oxygen is | | | | system. |
| present, producing gases that can potentially kill fish. | | | | Whatever planting medium you choose, this is only |
| Neither sand nor gravel on its own contains any of | | | | one important consideration when giving your |
| the chemicals needed by plants for healthy growth. | | | | aquarium plants optimum growing conditions. Correct |
| Over time, a combination of colonizing bacteria plus | | | | lighting intensity, water acidity and temperature must |
| accumulating fish faeces and plant debris (called | | | | also be provided to produce green and luxuriant |
| 'mulm') will gradually improve growing conditions below | | | | growth of your aquarium plants. |
| the gravel surface. Fully aquatic plants such as Elodea | | | | |