Im no expert on aquarium plants, but this is the basics about live tank plants that i know;
a. Live plants are good at lowering nitrates in your tank naturally, so if you have high nitrates adding them is very beneficial for the tank/fish.
b. Plants vary a huge amount as to how difficult they are to maintain, some are low-light plants that don't really require anything to grow while others need strong lights, CO2 boosts and fertilisers and a whole load of other stuff- for some info on commonly available easy to grow plants, check out the plant section
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c. As stupid as it sounds, not all aquarium plants sold in lfs are actually for aquariums- some need to be semi out of the water while others can't be submerged in any water at all, there are alot of plants sold that would die in your average fish tank in a couple of weeks.
The basic rule of thumb's to knowing if your plant is meant to be for a fish tank is
1. Can it support itself out of water? If so, this plant is not meant for your fish tank- almost all fish tank plants should not be able to support themselves upright out of water.
2. Are the plant's leaves variegated? I've noticed that many plants that have stripey leaves or leaves with patterns with more than one color are not meant for your average fish tank.
d. All plants can benefet from aquarium plant fertilisers, i use "Flora Boost" by interpet myself and is very good at helping my plants flourish. When you buy new plants its best to separate the plants up a bit as most will come in a clump of many when you buy them, this helps prevent the roots from rotting and gives them space to take hold, it can be difficult to plant new plants first time as their roots won't be very established so you may need to weight their roots down with some pebbles at first to stop them from floating around the tank
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For more info check out the plant section, there are many members on here that are experts at growing planted tanks and you can see some of their pics in the members aquarium section for inspiration
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