The filter starts to run slow. The water turn slightly cloudy. Something’s wrong and your inner voice yells at you to do something!
Grab a sponge and start scrubbing until it sparkles! That sounds like the correct response since clean is usually good… but, when you’re talking about a fish tank, it’s actualy your worst enemy. A filter is not like a dish to be washed.
It’s more than just about cleaning away grime. It’s about the biological engine that maintains life for your pet. That engine consist of colonies of beneficial bacteria that convert toxic ammonia into non-toxic substances.
How to Clean Fish Tank Filter Safely
The Importance of Beneficial Bacteria
Those bacteria are mostly on the filter media. Soaking them in hot soapy water and brushing them away will kill colony. This results in a spike in those very same toxins.
Which can crash your tank. It was clean, but not to clean. Remember, your objective is to clear out the junk while leaving the biological filter intact.
A shift in thinking are necessary. This isn’t a machine you’re cleaning, it’s a living system. Here’s how to do so gently without harming it.
Removing Filter Media Safely
Water choice and gentle touch is essential. Turn the filter pump off first. Carefully remove media.
Depending on what type of filter you use, you may be able to take the impeller apart while it’s still half in water. You can often do this if you’re using Eheim Classic or a Fluval 04 hang-on-back filter. That way the bacteria stays wet and alive.
Otherwise, if you’re using a canister or sump, you’ll want to remove the baskets/cartridges. Rule number one: Don’t let your media go dry. When exposed to air for too long, bacteria will dies very rapidly.
Keep the media moist, work fast. The type of water is much more important than you’d imagine. Don’t rinse with straight tap water from faucet.
Rinsing Media with Tank Water
Municipal water supplies adds chlorine (or chloramine) to kill bacteria. That includes good bacteria you don’t want killed. Tap water will immediately sterilize your media.
Use previously treated tank water from an existing water change. The water is at the same temperature and pH as your tank, doesn’t contain any chlorine, and is safest medium for rinsing. Rinse gently.
Don’t scrub. Use a ceramic ring or sponge to swish around in your bucket of old tank water and loosen up the debris that has stuck to media. Let it float free.
Rinse again. Again. Keep rinsing until the water in the bucket are clear.
The media won’t appear new or even white. It should still be somewhat dirty looking. In fact, all those little brown spots is what we call biofilm, home to your bacteria.
Is it too clean? Probably. Now you’re deciding how clean you want your sponge to look, even if it isn’t actualy pure.
You only want clear in the water. The key is timing your maintenance. Don’t clean out all your filter media at the same time.
Staggering Maintenance Routine
For example, if you use several layer of ceramic rings or sponges, clean one layer and leave the remaining ones in-place. That way, as long as there’s a healthy colony present, it’ll continue doing its job while you’re cleaning the others. Rotate which layer you clean every time you do some maintenance.
The staggered approach will keep your filtration capacity from dropping sudden. Lastly, clean your intake tubes or other mechanical pre-filters that catch the big stuff you see but don’t want to get into your biological media. You aren’t killing many bacteria here, if any, so you can cleans them thoroughly.
Just give them a quick rinse with some of tank water to remove the goop and put ’em right back together. Turn the filter on and listen to make sure everything is running smoothly. You must balance cleaning with keeping things alive.
When it comes to cleaning a filter, there’s a fine line between getting out the junk and still leaving some in there so you don’t kill everything off. It seems counter intuitive. Why would you want a dirty looking filter?
Because that filth is protecting your fish. Have faith. A little dirty sponge = a happy, healthy tank.
Your fish couldn’t give a crap if the sponge looks clean. They just need to feel safe. Let the bacteria work for you.
You’ll have crystal clear water as time goes by. It should of been done sooner.
