This topic has been debated among aquarists for years, and the answer often depends on your specific aquarium setup and fish species.
But, before we get into that in a bit more detail, I’ll get straight to the point.
Should I Turn Off The Filter When Feeding Fish? TL;DR
You shouldn’t need to turn your filter off when feeding your fish, but you can if you wish.
Presuming you’ve stocked your tank properly and have an established nitrogen cycle, turning your filter off for a short period won’t do any harm. You’re not going to cause an ammonia spike, you won’t deplete the oxygen for your fish, and your beneficial bacteria will be just fine.
If you need to switch the filter off due to the food being blown around and your fish are struggling to feed, I’ve gone over some solutions further down.
4 Pros Of Turning Off Filter When Feeding Your Fish
Turning off your aquarium filter while feeding your fish can have some benefits.
1. Reduced Water Flow
In strong currents, food can get blown around too much.
Some fish, particularly long-finned fish like bettas and fancy goldfish might struggle to catch food particles, resulting in poor feeding.
2. Prevents Food From Being Sucked Into The Filter
Any food that gets sucked into the filter can not only cause waste buildup but also reduce the efficiency of the filtration process.
But, that’s not necessarily a bad thing. A small amount of fish food getting sucked into the filter will break down and feed your beneficial bacteria, it’s only problematic when it stops the filter from working efficiently because it’s full of gunk!
3. Food Can Sink To The Bottom
Different fish hang out in different parts of the tank. Bottom-dwelling fish can miss out on their food if the water flow from the filter’s output keeps it circulating higher in the water instead of allowing it to sink to the bottom of the aquarium.
4. Saves Energy
With the ever-increasing energy bills, more and more people are looking at ways to cut back on their energy usage, and turning it off occasionally may help save energy and reduce your electric bill.
3 Cons Of Turning Off Filter When Feeding Your Fish
For every pro, there’s always a con.
1. Reduced Water Flow
Different species of fish live at different levels in the tank, and each has its own territory.
The filter outflow nozzle is designed to circulate the water through your tank.
This ensures food gets spread around the tank so all fish can get at it, not just those that are super greedy, fast swimming, or those in the right place at the right time.
2. Food Can Sink To The Bottom
Any food that’s allowed to settle at the bottom of the tank can become embedded in the substrate and begin to break down, releasing ammonia into your water, with is harmful to fish.
This isn’t an issue if you have bottom-dwelling fish that can gobble it up.
3. You May Forget To Turn The Filter Back On Again
This is me! Other than for maintenance, I don’t turn off my filters.
I can be a real forgetful some days, and there’s a good chance I’ll forget to turn it back on again!
If you forget to turn your filter back on, the oxygen levels can drop, and ammonia levels can rise which will cause stress to your fish.
4 Easy Solutions
Now we’ve gone over the pros and cons, let’s look at some practical solutions if you are having issues when feeding your fish with the filter switched on.
1. Reduce Water Flow
If you are having to unplug your filter because of water flow, it may be that the filter is too powerful for your tank.
You need to ask:
- How big is your tank?
- What is the turnover rate of your filter?
The general rule of thumb is 4-6 times the volume of water in the tank per hour
You should adjust the flow rate if you can, or turn the output nozzle so it faces the corner or edge of your tank to reduce the current.
You could also rearrange tank decor items, or add a few if you have space, to help break up the water flow.
2. Stop Food Being Sucked Into The Filter
You can fit your filter intake tube with a pre-filter sponge.
Sure the food will get stuck on the sponge, but your fish will soon find it and eat it off the sponge.
3. Forgetting To Turn The Filter Back On
If you establish a set time of day to feed your fish, you can use programmable timers so your filter will shut down and restart automatically.
The BN-LINK pack of 2 24-hour timer switches are great value for money.
Use with any electrical items on your aquarium that you don't want to run 24/7.
You'll never have to remember to switch off your aquarium lights again, helping avoid the dreaded algae bloom!
Note: This can be an issue with some older HOB filters as they do not self-prime and need some water to be poured into them to get them going.
4. Stop Floating Food Being Blown All Over
If you’re feeding food that floats, there’s the option of using a feeding ring to keep it in one place, making it much easier for your fish to eat.
Should I Turn Off The Air Pump When Feeding Fish?
An air pump’s job is to create surface agitation, allowing the gas exchange process to happen, which keeps sufficient oxygen in the water.
I wouldn’t turn off an air pump either, but you can if you want to. Just remember to turn it back on again, or use a programmable timer and have it shut down and restart simultaneously as your filter.
Closing Thoughts…
Shutting down your filter at feeding times has its pros, but it’s not something I choose to do when feeding my fish.
There is no right or wrong answer here, it’s your aquarium, so it’s entirely up to you.
Just bear in mind if you forget to turn it back on, the water conditions will deteriorate as oxygen levels drop and ammonia begins to build up.
For that reason alone, I never turn my filters off other than to clean them.
Check out the aquarium health section for guides and tips to keep your aquarium in tip-top shape.
Related post: Can Fish Sleep With The Filter On?
