It’s pretty easy to grow houseplants in aquariums – they tend to come pre-lit, they’re naturally humid, you don’t need to water, and the fish provide the fertilizer. The only difficult thing is working out how to keep the leaves out of the water. Most plants will grow in water, but stay away from any plants that don’t like humidity, such as cacti. Christmas cacti can do pretty well though, and they bloom more reliably than ‘dry’ cacti.
What About Not So Furry Friends?
In this case, we are particularly talking about freshwater fish. Don’t put plants in a marine setup – they will simply pass away. That being said, you can put plants in goldfish tanks, but they will eat them. A lot of people also advise against keeping house plants in with angelfish because they eat the roots, so keep that in mind. Some fish need a lid on the aquarium because they jump out. If you want house plants in the aquarium and have jumpy fish, you’ll have to lower the water level (providing the fish would have enough space) or get a bigger tank.
Step By Step
Cleaning off the roots well is so important when putting plants in any water, but even more so when they’re going into an aquarium. Soil can contain microbes and other gross things that could potentially harm your plant. If you have a specific plant that you want to grow in your aquarium but you can’t get the roots clean enough, take a cutting and root it in the tank. You don’t want to risk your fish. Plants root really quickly in aquariums – especially tropical ones – because they naturally combine all the elements required for rooting cuttings in water quickly. The water is well-aerated, warm, clean, and it’s humid.
Light can be an issue with aquariums because if you have big plants, the lights will be below the plant. You might think that that’s ok, because there’s ample natural light in the room BUT sometimes plants want to grow a certain way and end up curling under a grow light and inevitably both burning and falling into the water and rotting. You can clip a couple of grow lights on the back of the tank that are taller than your plants. Peace lilies actually grow really well in aquariums and tend to grow up, rather toward the light.
Now, most plants will do well in aquariums unless they hate high humidity, but some are physically more suited to it than others. If you’re new to adding house plants to fish tanks, then start with something that trails. A pothos or a rhaphidophora tetrasperma will be good to start with. Also syngoniums and Philodendrons. Over time, you’ll notice holes appearing in your plantscape, and you can add plants to fill the space. The hardest thing is keeping the plants upright. For large plants, it’s usually best to anchor them properly.
Something to note is to not submerge your plants. There are some plants, like Monstera adansonii, that you can submerge, BUT it’s not as easy as sticking the plant underwater and being done with it. Most house plant leaves will rot. You need to keep them out of the water. You can also float them in slices of pool noodles, or stack rocks (but make sure they’re secured with aquarium-safe glue and aren’t going to trap your fish).