What Causes Rust in My Fish Aquarium?

An aquarium is a highly controlled and constructed environment, and rust is something that can ruin the balance that you are trying to achieve. Many novice aquarium keepers notice that they have rust in their aquarium and that it is negatively affecting their fish, but they may not know where the rust is coming from. Consider what the source of rust might be in your aquarium.

  1. Silk Plants

    • Silk plants look great in aquarium setups, but they often have a metal wire core that helps the stem remain upright. Over time, the wrapping over the metal will fray or abrade, allowing the wire to make contact with the water. This can put a small to moderate amount of rust in the water. Most hobbyists prefer to use plastic plants for this very reason.

    Play Sand

    • If you use play sand in your aquarium, you can expect to get some iron contaminants. They might be invisible until you put the play sand in the water. At that point, you might notice small specs of reddish brown or dark brown sediment mixed in with the sand. This is very apparent when you have bought pure white play sand.

    River Sand

    • River sand is also called beach sand, and it normally consists of granite and quartz. Typically, it comes with a small amount of calcareous material mixed in. There is a possibility that river sand contains some iron sediment in it, and when it comes in contact with your aquarium, the iron will start to rust.

    Rocks

    • Many people simply bake rocks that they find to remove parasites before putting them into the aquarium, but this will not remove iron contained in the rock. If the aquarium rocks that you have found are creating rust in your aquarium, remove them from your setup. Some people chose to use only aquarium rocks in their setup or to keep their aquarium settings minimal.