Aerating the water in the tank is important because it helps to circulate the water and also replenish the oxygen in the water as well as removing some carbon dioxide.
If you have a heavily planted tank, this may not be necessary to aerate the water with an air stone as plants produce oxygen and use up the carbon dioxide during the day. But the pump attached to an air stone will be needed at night as plants also use up the oxygen and release carbon dioxide.
If you do not use air stones, if you decide to keep moving ornaments in your tank then these will need a pump to move them.
Please note tubing and ornaments or air stones need to be purchased separately.
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