Humans have taken some big steps in recent years to acknowledge our detrimental effect on world climate and ecology. Thankfully, many of us are now trying to reduce our ecological impact, but how does this affect fishkeeping?
Keeping an aquarium can indeed leave a significant footprint on the planet’s ecology, yet there are several practices that more and more people are adopting to lessen the impact. Here we’ll be sharing some of the most important ones.
Choose Tank Bred Fish
Sadly, many species of wild fish are not as common as they used to be. Pollution, climate change, overfishing, and even harvesting for the aquarium trade have taken their toll on so many species. If you don’t want to make this crisis any worse, your easiest option is to choose captive-bred fish.
Not only are fish raised in farms and tanks more sustainable than wild-caught specimens, but they also grow up in a captive environment, so are well-adapted to aquarium conditions. Captive-bred fish have a reputation for being more robust and hardy, so are more likely to live longer lives in an aquarium.
Always ask your aquarium store where the fish were sourced before buying. If they can’t tell you or they don’t seem trustworthy, wait until you find a more reliable outlet. Another great way of sourcing captive-bred fish is to go directly to the breeders. Thankfully, many fish breeders are now easy to find online, and you may even be able to select specimens with unique characteristics.
The only hitch with buying tank-bred fish is that not all species are easy or even possible to breed in captivity! In such cases, you may have to do more research to find sustainably wild-caught specimens.
Choose Sustainably Caught Fish
If you have your heart set on keeping a type of fish that cannot be bred in captivity, your next best bet is to try finding specimens that have been sustainably caught.
There’s a vast array of ways that wild fish are harvested from the world’s lakes, rivers, and seas for the aquarium trade, some of them more ethical than others. Harvesting wild fish from coral reefs is especially notorious for its destructive impact. According to a report from The Guardian, mortality rates can sometimes reach 80%.
In the best case, however, small numbers of abundant fish species are caught in a permanently sustainable way. Ecological harvesting of tropical fish may even benefit local people in impoverished regions – but you must do your homework.
It may take significant research and effort to buy fish caught by such responsible methods, but once again, the internet has made it easier to connect with ethical suppliers. You may also find it enriching to know exactly where your fish came from.
Use Energy Efficient Equipment
With the increasing depletion of fossil fuels, rising CO2 levels, and the climate crisis looming ever larger, many aquarists are considering how they can reduce their energy footprint in their aquarium.
The good news is that tropical fish turn out to have a lower carbon footprint compared to keeping many other pets. A recent scientific study from Northern Europe concluded that even tropical fish tanks produce less CO2 than keeping either a cat or dog!
But that doesn’t mean we can’t do more to reduce our energy consumption further. Fish keepers wishing to keep eco-friendly tanks can choose long-lasting LED bulbs and energy-saving filters, and may even consider cold water aquariums to remove the energy-hungry heater from the equation.
While goldfish and guppies are well-known coldwater species, you may be surprised to learn that Japanese rice fish, zebra danios, cherry shrimp, bloodfin tetra, white cloud mountain minnows, and bristle nose plecos can also tolerate temperatures down to 65°F – so can go without a heater in a warm room!
Eco-Friendly Substrate and Decor
When it comes to aquarium substrate and décor, some options are much more ecologically friendly than others. While gravel and sand are usually sustainably sourced, more care is required when choosing substrates that contain crushed coral.
Although crushed coral is an effective pH buffer that can be useful for making water harder and more alkaline, it’s not always harvested in an eco-conscious way. Instead, consider using limestone as an effective pH buffer. Because it’s much more abundant than coral, limestone is more likely to be sourced sustainably.
Additionally, consider choosing décor that’s local to you. While there are all kinds of exotic rocks and synthetic décor you can buy, the local rocks, stones, and driftwood in your locality are likely to be highly suitable, too.
It can be especially rewarding to decorate your tank with items that you’ve found while out walking. As long as you check that it’s legal to collect them, that they’re aquarium-safe, and wash them thoroughly, they can make a unique and original addition to your tank.
To find out more about which types of rocks and crystals are safe for aquariums, check out our dedicated guide here.
Watering Plants With Aquarium Waste Water
One last ecological trick that we’ll touch upon is the best way to reuse aquarium wastewater.
With water resources becoming ever more scarce in many regions, people are coming up with all kinds of ingenious ways to repurpose wastewater so that it can be used again.
While you might struggle to imagine what the brown, cloudy liquid sucked up after hoovering your gravel could be useful for, aquarium waste water and plants turn out to be a match made in heaven!
Packed full of nitrogen, potassium, phosphorus, and other important plant nutrients, wastewater from your tank makes an excellent fertilizer to give your house plants and ornamentals a welcome spurt of growth and healthy-looking, glossy leaves.
Just avoid watering vegetables and edibles – especially salad leaves with fish tank water. Aquariums sometimes contain harmful pathogens that can infect humans if we ingest them. To be on the safe side, reserve your dirty tank water for ornamentals or fruit trees only!
