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Take care not to damage the plant as you remove it from its packaging, and carefully plant it in the substrate according to the planting instructions. Different types of plants require different depths to be planted in the substrate — some common methods for different plant types include:  Mosses and Grasses: Turn off the filter, and place the moss directly on top of the substrate in areas you want it to grow. Place a heavy coin, such as a half dollar or pound coin, on top of the moss to keep it down while the roots grow into the substrate over the next week. Potted plants: Remove the plant from the plot and be careful to not damage the roots poking out of the bottom of the dirt or cotton. Dig a hole in the substrate as wide as the plant, place it inside, and then blend in the sides of the plant with substrate. Ferns: Attach the fern to a rock or piece of driftwood with a fishing wire or cotton thread to keep it upright. Ferns do not need to be placed in the substrate layer, most just need something solid to hold onto for stability. Cotton thread will dissolve with time, whereas fishing wire should be cut away and removed once the fern takes hold. Plants with a stem: Push the base of the stem about 1–2 in (2.5–5.1 cm) into the substrate and it should stay upright. If not, use a fishing wire or cotton thread to keep it up until it can support itself. You can plant stemmy plants all in one area in a frilly bunch, or spread them around the back and middle areas. Plants of all kinds can quickly become too big and take up too many resources in the tank for their own good. Use a very sharp knife to cut away dead leaves, dead stems, and trim the grass or moss in the tank every time you clean the aquarium.  Moss can be re-planted in other areas of the tank, if you wish, by simply placing it onto an empty patch of substrate and weighing it down with a heavy coin until the roots take hold. Take about 2 in (5.1 cm) off of the top of a stemmed plant to encourage its growth when it gets to reach the top of the water level. Substrate, plants, and everything else you've put into the aquarium can change the acidity, nutrient content, and overall healthiness of the tank. Allow the tank to cycle water normally through the filter, remove algae and buildup, and allow the plants to take root before you introduce fish and aquatic animals.  The tank needs time to build up nutrients and beneficial bacteria in the substrate. This beneficial bacteria helps to stabilize the tank and prevents ammonia and nitrate build up. Especially with bottom feeding and burrowing aquatic animals, it is important to let your plants get to the point that they can support themselves before you introduce new creatures. Some aquatic pets will dig at the base of plants, or eat leaves and stems, so you give your plant the best chance of survival if you allow it to take root.
Remove your plant from its container and set it in the substrate layer. Trim your plants regularly to encourage their growth and survival. Let the tank cycle water for about 1 month before you introduce your fish.