You might not have ever expected to have to change the water in aquaponics, but part of cleaning aquaponics setups is keeping up with water quality.
An aquaponic water change is a useful tool for preserving the conditions your fish need to stay happy and healthy.
To know when a water change is necessary, it’s helpful to test your water quality often.
Once you’ve deemed that a water change is needed, it’s best to do so slowly and only for small amounts.
Conversely, if you know frequent water changes are something you’ll be doing ahead of time, an automatic valve makes everything so much simpler.
Certain species of fish are going to need water changes more frequently than others, but ultimately when and how are factors that are going to depend on your individual system.
In this article, we’ll be discussing water changes as well as when and how to do one without harming your aquaponics system.
Monitor Water Quality Often
How often you check your water quality is going to depend on several factors.
What kinds of fish your raising, the size of your grow tank, and even the color of your water all play a role in how often you check on the environment your fish are living in.
A species like a tilapia will probably do fine with weekly checks or less.
Whereas with more sensitive species like perch and trout, daily water checks are for the best.
This can tell you everything from the pH of your water to the temperature.
Interested in learning more about pH? We have explained pH in high detail check out our article by clicking here.
That knowledge, in turn, allows you to best gauge when an aquaponic water change might be necessary.
To be clear, when we talk about the time to change the water in aquaponics, we don’t mean just topping off whatever’s evaporated.
A tank that’s lost water due to evaporation is simply more concentrated with pollutants than it was before.
Adding more water could help, but a proper water change means taking water out and replacing it with fresh.
Change Your Water Out Slowly
When you’re cleaning aquaponics, it pays to remember that slow and steady wins the race.
Aquaponics is a balanced system that the idea of taking something out and adding something new, it can be a little nerve-wracking.
But sometimes performing a water change can be necessary.
If you feel like you need to switch out some water for the health of your fish, do so gradually.
Often that means no more than 20 or 30 percent of the entire tank per day until your water is replaced.
In a hundred gallon tank that’s just 20 or 30 gallons.
For your typical 300 gallon drum that’s going to be about 60 to 90 gallons that you’ll take out and then slowly pour back in.
Depending on the issue and how sensitive your chosen species of fish is this can take hours.
On a rare occasion, you might want to replace as much as 10 percent of the water.
However, this should only be done in emergencies or with extremely hard fish species.
Many fish find handling sudden swings in pH to be incredibly stressful.
Are you looking for a siphon to help keep a well balanced aquaponic system? Check out our recommended siphon on Amazon
An Automatic Valve Makes Water Changes Simple
If you don’t really have that much time or you’re not as confident in your ability to be patient enough to do a slow water change, then you might want to consider adding in some automation.
While this is certainly more expensive, if you plan to do aquaponics for the long haul, then an automatic valve that drains and refills tanks the right amount for you is an invaluable tool for cleaning aquaponics.
This is especially true if you intend to turn your aquaponics setup into a commercial business.
There are ready-made systems that have been designed specifically for fish that can empty and refill a preprogrammed amount of water either on a timer or at the flip of a switch.
If you happen to be a little savvier with mechanics, then you can also design your own system.
Not only will an automated system save you time, but the precision of it can also save you money.
Are you interested in an Automatic valve? Check out our article where we explain your options in high detail!
If you want to buy one from Amazon this is our number one recommended click here.
Water Changes Might Be Necessary for Certain Fish Species
We’ve talked about some species being a bit more sensitive to water quality, but there are actually species of fish out there that require you to change the water in aquaponics to grow properly.
These are usually are species like koi or goldfish.
Their waste isn’t just made up of ammonia and solids and also contains an inhibiting growth hormone.
In fact, this is the reason for the myth that these fish will only grow to the size of their tank.
A goldfish in a smaller tank is living with more concentrated amounts of their own waste and therefore grows much more slowly.
Though they do still grow.
While filters and a few very specific species of plant can help take away some of that chemical, the only way to get rid of it entirely is through weekly water changes of about 3 to 10 percent.
Other species, like perch and trout, are simply much more sensitive to water quality and do best with careful monitoring along with any needed aquaponic water changes.
Not All Water is Created Equal
When cleaning aquaponics, it’s best not to forget that not all water is the same.
If you live more in the city and don’t have your own well, then chances are there are chemicals in your tap water.
Typically, city water contains a significant amount of fluoride and chlorine.
While this keeps the water clean for the masses, it’s deadly for fish.
In this situation, it’s best to find an outside source of water even if that means buying spring water in gallon jugs from your local supermarket.
There are also companies out there that bring in water to fill pools.
Using one of these to do at least the initial fill of your tanks can be a much more cost and effective time option.
Reuse the Water on Soil Based Gardens
If you’re running an aquaponics system, then chances are you love the sustainability of it.
Nothing goes to waste.
So the idea of simply dumping such a precious resource like water onto the ground feels wrong.
Instead of simply tossing it, when you do an aquaponic water change, you can always use this rich resource to water a soil based garden.
Not only does this allow you to effectively change the water in aquaponics, but it’s still putting your fish and their naturally fertilizing capabilities to good use.
Temperature Can Play a Factor in Aquaponic’s water quality
Cleaning aquaponics can be a scary process.
There are certainly fish enthusiasts out there who’ve stressed or even lost some of their stock to improper water changing methods.
One of the elements that people often forget is temperature.
For tilapia, replacing some of their lovely, toasty habitat with something akin to ice water is going to seriously impact their health.
Similarly, putting warm water in a trout tank is going to give you a bunch of fish who suddenly won’t eat because they’re too hot.
Much like a sudden swing in pH levels, a quick shift in temperature can seriously harm your fish.
To avoid this problem, you can leave your water in the same environment as your grow tanks for as long as is needed to even out the temperature.
If you don’t have enough time for that, then heating or cooling the water mechanically until it’s at the right level can go a lot quicker.
Add More Plants for Fewer Water Changes
If you really don’t want to have to change the water in aquaponics, then consider using a significantly larger plant portion of your growing system.
Plants consume contaminants in the water and help keep your system balanced.
More plants to fewer fish mean a more consistent water quality and less need for an aquaponic water change.
Conversely, you could also feed your fish a little less or spread their feedings out across several times in the day.
This way, you can still give your fish plenty to grow off of while making sure they leave less wasted food on the bottom of the tank.
In other words, it may sometimes be necessary to change the water in aquaponics.
Monitoring your water quality can help give you a bit of a heads up on when it’s time.
Not every setup will require them, but if you do have to take out and replace some water when you’re cleaning aquaponics, keep it slow.
An automated system can help make aquaponic water changes a breeze.
But even changing the kind of fish you raise can significantly affect the number of water changes you’ll need to do.
Keep in mind that not all water is the same, but you should still be trying to keep at least the same temperature when adding new water in.
How can limit the number of water changes in aquaponics? Simple, Do not add as much fish or add Biofilter and/or Swirl filters. We can help you check out our article about Aquaponic filters.
Will too much sunlight require me to do more water changes? Yes, excessive sunlight directly hitting fish tank will ammonia to grow at a much faster. Painting the surface black can help slow down the growth rate.
What equipment shall I require for aquaponic water change? It is possible to do this with just a hose. To create suction a vacuum can help. We recommend you check out this hose designed for aquatic water changes, check it out on Amazon!