Choosing the plant and animal life for an aquarium is tricky work. On one hand, you want it to look as gorgeous as possible. But on the other, you don’t want to use plants or fish that might make each other sick. So, can the supposedly “toxic” philodendrons grow while immersed in your aquarium?
Philodendrons cannot grow fully immersed inside an aquarium, but they can participate in an aquarium ecosystem if you allow their roots to grow in the water. While philodendrons are toxic, their toxicity won’t affect your fish as long as the leaves stay out of the water.
Philodendrons are fun plants, and if you do it right, you’ll be able to utilize them for your aquarium, making a tank that both you and your fish will be sure to love.
The name “Philodendrons” doesn’t actually refer to one specific plant. There are around four-hundred and fifty species of philodendrons, so saying that all philodendrons like spending their lives submerged in water just isn’t true. The two best philodendron species for water systems are the Heart-Leaf Philodendron (Philodendron cordatum) and the Velvet-Leaf Vine Philodendron (Philodendron micans).
Velvet-leaf vine philodendron and heart-leaf philodendron are both remarkably similar, with a couple of key differences. The main difference between these is their appearance and growing style. Velvet-leaf vine philodendron will grow out horizontally, whereas the heart-leaf philodendron will usually shoot straight up (if they can). Heart-leaf philodendron also have a lighter, brighter green, while velvet-leaf vines have a velvet-like texture with a more evergreen color.
No matter which one you pick, both the velvet-leaf vine and heart-leaf philodendron are some of the easiest houseplants to grow. Either of them would be the perfect aquarium plant option if you want to spend most of your energy focusing on your fish.
Philodendrons and Water
Freshwater or Saltwater?
Something important to note before buying a philodendron for your aquarium is what kind of aquarium you have. Is it for freshwater or saltwater fish? Plants have preferences on the water they’ll live in, just like most fish, and philodendrons are no exception.
Some types of philodendron are saltwater tolerant, but for the most part, heart-leaf and velvet-leaf vine philodendron plants should stay as far away as possible from saltwater. When heart-leaf philodendrons are grown in soil, their leaves will burn (aka start crisping up and turning brown at the edges) due to the build-up of salt from tap water. Heart-leaf and velvet-leaf vine philodendron do not do well in saltwater. Putting them in your saltwater aquarium is a good way to kill them pretty quickly.
The only philodendron that is known to be saltwater tolerant is the split-leaf philodendron (which is actually a monstera plant, not philodendron). If you have your heart set on putting a philodendron in your saltwater aquarium, then the only one that will actually survive is the split-leaf philodendron, even though it’s not as pretty as the heart-leaf or velvet-leaf vine. But there are plenty of other plants that survive and thrive in saltwater. Click here to see the top ten most popular saltwater plants to put in your aquarium.
No, philodendrons can’t and won’t survive being fully immersed in water. You can’t plop that sucker at the bottom of the tank and expect everything to go swimmingly.
But, philodendrons absolutely love having their roots submerged in water, as long as the leaves and vines are in the open air. Philodendrons will spring to life as their roots spread in the water, making for a cool visual and nice little treat for your fish to nibble on. Even people without aquariums will often plant their philodendron in little glass jars full of water because it works so well.
Philodendrons are plants, and as such, they need nitrogen to survive. Lucky for you, that means that if you put philodendrons in your tank, they’ll not only be pretty, but they will also help clear out nitrogen-based toxins for your fish. They will clean out toxins such as nitrite, nitrate, and ammonia.
They don’t get rid of toxins that underwater plants get rid of, such as large CO2 concentration, but you can just get some underwater plants to pair with the philodendron to have all the bases covered. When your plants and fish work together, it can make for a happy and healthy aquarium environment.
There are plenty of internet rumors circling about that claim how you should never put philodendron or pothos in your aquarium since they can “ruin” the whole system. One YouTube video claims that a “Pothos DESTROYED my aquarium!” when, in fact, the pothos they added only got rid of the black algae in their aquarium (and all the fish were totally fine).
Philodendron and pothos are living creatures, so when they’re brought into a new ecosystem, they might edge out some other plant species. Unfortunately, that’s just how natural competition works. It’s survival of the fittest. And philodendron are so good at sucking nutrients out of the water that they might make it harder for other plant life to survive.
This has never been a problem with fish, though. Just make sure to monitor plant life after adding a philodendron to your tank.
Unfortunately, the rumor about philodendron being toxic does stem from truth. Philodendrons are toxic, at least, to a certain extent. Their roots aren’t toxic, and putting them in an aquarium with a bunch of bright fish won’t hurt them a bit. But their leaves contain oxalic acid, which is toxic to humans and animals alike. This is why it’s especially important to keep the leaves out of the aquarium water.
Not only will the other plants die, but if the fish start nibbling on the leaves, they’ll turn belly-up too.
If you do add a philodendron to your aquarium, be wary of your wandering house pets (especially cats and dogs). Make sure the aquarium is far enough off the ground so that a curious cat or nosy dog won’t be able to reach the leaves and take a bite.
When ingested by humans or animals, philodendron leaves can cause mouth, tongue, and throat swelling (which makes it kind of hard to breathe). In extreme cases, it can also cause vomiting and diarrhea.