Plants are great for aquariums; they create oxygen for your fish, keep your tank clean and simply look good. But beware – Pet stores often try to make money by selling terrestrial (land-dwelling) plants as aquatic ones. Though water is good for plants, submerging terrestrial plants in water is a bad idea. They will die and rot in your fish tank. The pollutants from the rotting plant are likely to cause your fish to die. When aquatic plant shopping, make sure you only buy true aquatic plants. Here are brief descriptions of plants pet stores most commonly try to sell as aquatic wannabes.

The most popular is the Dracaena Marginata, or Dragon Tree. Dragon Trees kind of look like paint brushes, with trunks similar to palm trees and spiky leaves that stick out of the top. Your friendly neighborhood pet store usually sells a baby version of this tree, but in the wild they can grow to be 16 feet tall. Dracaena Marginata is considered a bamboo plant and actually needs dry conditions to grow and will die rather quickly if submerged in water.

Another popular poser is Algaonema. This is actually a popular household plant and is recognizable by its wide green waxy-looking leaves. The Chinese believe this to be a good omen, but could mean bad things for your aquarium. Algaonema need to be planted in heavy soil that is moist, not soggy, and will die rapidly in water. Furthermore, they are poisonous and cause a rash in your mouth and throat if ingested orally. So imagine what happens when it begins to rot in you aquarium after just a few weeks!

The Brazilian Sword, or Peace Lily, is another one to avoid. The Peace Lily looks like the Argentine Sword, with long thin stems a few wide spade-shaped leaves. This plant actually asks for dry conditions to grow. It will take a long time to die in your tank, but nevertheless should not be placed with your guppies since it can not thrive and will start dying before you even realize it. The previous article discussed that Amazon and Argentine Swords were great aquatic plants-but just because “sword” is in the name does make it a good plant to live with your fish!

Cherry Hedge and Green Hedge are other terrestrial plants that sneak their way onto pet store shelves with genuine aquatic plants. They will all do fine for a long period of time but will die off after several months at the most and should not be submerged in water. Cherry and Green Hedges have a similar appearance. They are both short, bright green, and bushy. The Green Hedge does have smaller leaves than the Cherry Hedge. These plants are hardy but need dry conditions to grow.

Mondo Grass certainly appears exotic. It comes in bush form and looks like a bunch of pale green grass. This is a terrestrial plant that needs little care. It simply needs very little watering and soil that drains well. Due to its drier needs, Mondo Grass usually takes only two months to die if submerged in water.

Lastly, White and Red Arrowhead are other evil beauties that will doom your fish habitat to extinction. Arrowheads are tall plants with thin stems and arrowhead shaped leaves at the top. White Arrowheads are more of a pale green, while Red Arrowheads have dark green edges and reddish centers. Their natural habitat is near lakes and ponds, but it is a bad idea to put them in water as they will die rapidly.

The need to do the appropriate research before buying anything for your aquarium can not be stressed enough. Also, take care of the right plants, so they will not become the enemy. Trim them so they do not overgrow and hide your fish. Limit the tank to two floating plants. Oxygen comes in through the surface, and having too much plant growth above the fish could choke them. Follow the rules, do your research, do not fall for buying a terrestrial plant no matter how many pet store clerks say it is okay, and you will have a very healthy and natural-looking habitat.