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Should You Use Hydrilla In An Aquarium?

The hydrilla plant has been in the news again a lot recently because it is an invasive species with an exponential growth rate while being a surprisingly tough and robust aquatic plant.

Anytime hydrilla gets a lot of attention in the media, we see a spike in the number of questions that we see from the fish keeping community about using hydrilla in aquariums.

Although the main reason that we see people reaching out and asking about keeping hydrilla in their aquariums is due to it being readily available in a large number of places and being free, some people do like the look of the plant too.

Depending on the fish or other animals that you keep in your aquarium, hydrilla can sometimes serve as a supplementary food source too helping to keep your costs down by using it for food for your fish too.

Due to seeing so many different questions about using hydrilla on a regular basis, we have decided to publish this guide going over using hydrilla in your aquarium to try and help as many of our readers as possible.

As we see so many different questions about the plant, we have decided to add our table of contents below to try and help our readers quickly navigate the article to get to the specific sections that they need information for as quickly as possible.

Should You Use Hydrilla In An Aquarium?

Although you can use hydrilla as a plant in your aquarium, you have to realise that is does grow extremely fast with the majority of aquariums presenting the perfect growing conditions for hydrilla.

This will often result in a huge amount of maintenance being required for hydrilla to be properly controlled, especially if you are wanting other plants in the aquarium as well as a large number of fish too.

Having hydrilla in your aquarium will add a surprising amount to the overall bioload for the tank due to it absorbing a large amount of nutrients from the water.

Although this is unlikely to have any direct effect on most types of fish, it can cause problems for some of their other popular aquatic plants that people like to keep in their aquariums.

That said, keeping hydrilla in your aquarium presents a different risk to your fish due to the amount of oxygen it is able to remove from the water, especially once it is growing at a rapid pace and occupying large amounts of your aquarium.

If you do keep a large number of fish in your aquarium and have hydrilla in there then you may have to pick up a cheap oxygen pump to ensure there is plenty of oxygen for your fish but this will also increase the growth rate of the hydrilla even more.

Is Hydrilla Illegal?

Hydrilla is one of the most problematic aquatic weeds on the planet and is one of the main invasive species in North America and Europe.

Due to this, many law enforcement and environmental agencies have made hydrilla illegal in many areas with fines often being high due to it being such a problem.

We often see people asking about using hydrilla in their aquariums totally overlooking the legality aspect of hydrilla but many areas have legislation in place where it is illegal to transport hydrilla in any way.

If you are trying to get your own hydrilla from a public waterway that has rangers patrolling then they are able to give you an on the spot fine if they find you removing hydrilla, even if it is just for your aquarium.

Although rare, some areas have legislation in place where you can be fined just for having hydrilla in your possession due to people throwing it down drainage holes and it causing a number of problems in urban areas too.

Due to this, you should always check the laws and regulations in your local area if you are thinking of adding some hydrilla to your aquarium.

Does Hydrilla Produce Oxygen?

Although hydrilla does produce some during the night, it consumes a huge amount of oxygen relative to its size during the day due to its requiring a large amount of oxygen to maintain its rapid growth pace.

This will often cause any fish or other animals in the aquarium to become lethargic and require you to remove the hydrilla from the tank to return things to normal.

As we touched on above, some people do choose to add a cheap oxygen pump to their aquarium to try and offset the amount of oxygen that the hydrilla absorbs from the water.

Although this can help in some cases, it will also increase the growth rate of the hydrilla resulting in you having to do more tank maintenance to keep its growth under control.

This coupled with the potential legal issues in many areas is why so many people simply choose to use any of the other popular aquarium plants for their tank instead of hydrilla.

We would highly recommend that our readers take this option too as once hydrilla has a foothold in your aquarium, it really can be a pain to remove it fully with it often coming back over and over again if you accidentally leave a tiny piece in your aquarium.

What Is The Use Of Hydrilla In An Aquarium?

Hydrilla offers no real advantage to your aquarium that can’t be done better by an alternative plant.

The majority of the alternative plants will also have none of the disadvantages of using hydrilla in your aquarium too making them a much better option for most people in most situations.

This is why we recommend that our readers go with other popular aquarium plants for their aquarium instead of hydrilla as it really does make your life so much easier.

There are much better plants available to use for cover for smaller fish and fry or to oxygenate the water or to use as a supplemental food source that are much easier to manage.

Like we touched on earlier in the article, one of the main things that we see people saying about hydrilla time and time again is that they are able to easily get it for free from a local waterway.

Considering most of the alternative aquatic plants that people keep in their aquarium can be purchased for cheap, getting hydrilla for free really is not a good enough argument for adding it to your aquarium.


That brings our article going over using hydrilla in your aquarium to a close. In our opinion, you really should be doing your best to avoid using hydrilla as it causes more problems than it solves. On top of that, it can be a real pain to get rid of once you have added it to your aquarium and there are plenty of reports from people on social media who found this out the hard way.