Rinsing filter media in tap water, fact or fiction?

[Scott P.]

Interesting video by Jason at prime time aquatics.

I am not trying to change any minds, I just don't believe all the myths out there.

[ACW]

From what I've read and heard, 90+% of the beneficial bacteria in an aquarium is in the substrate, so rinsing your sponge filters in tap water doesn't make a huge difference. That said, I don't rinse ALL my sponges in tap water on the same day, just in case.

Of course, in a bare-bottom tank, I'd use tank water.

[ARMYVET]

I dont have any substrate...so tank water it is for me!!

[Guppysnail]

On 9/17/2021 at 1:22 PM, ARMYVET said:

I dont have any substrate...so tank water it is for me!!

Me too 4 of 6 bare 2 less than an inch tank water for me. I doubt tap kills all the BB or it would be considered a good sanitizing solution but without substrate each microscopic bacteria is precious to me. Me preciousssss 🤣

[JettsPapa]

On 9/17/2021 at 11:51 AM, ACW said:

From what I've read and heard, 90+% of the beneficial bacteria in an aquarium is in the substrate, so rinsing your sponge filters in tap water doesn't make a huge difference. That said, I don't rinse ALL my sponges in tap water on the same day, just in case.

Of course, in a bare-bottom tank, I'd use tank water.

I hadn't heard that, and while I'm not saying it isn't true I am skeptical.

I do believe that it's okay to rinse filter media in tap water if it's from a well established tank, but wouldn't recommend it for new tanks.  I don't doubt that a small amount of bacteria gets killed of when rinsing in chlorinated tap water, but I don't think it's much.

[ARMYVET]

On 9/17/2021 at 1:46 PM, Guppysnail said:

Me preciousssss

[Deku-Corydoras]

On 9/17/2021 at 12:51 PM, ACW said:

From what I've read and heard, 90+% of the beneficial bacteria in an aquarium is in the substrate, so rinsing your sponge filters in tap water doesn't make a huge difference. That said, I don't rinse ALL my sponges in tap water on the same day, just in case.

Of course, in a bare-bottom tank, I'd use tank water.

I hear everything from "most of the beneficial bacteria is in the filter and there's very little in the rest of the tank" to "there is very little beneficial bacteria in the filter and most of it is in the tank." Honestly I imagine it varies a lot depending on the tank, filtration, and substrate, which would explain why there's such a wide range of opinions. 

[anewbie]

Most of the beneficial bacteria is in the filter; but tap water won't hurt it unless you like leaving it soaking in hot water for a few hours.

Edited September 17, 2021 by anewbie

[ARMYVET]

On 9/17/2021 at 2:28 PM, Deku-Corydoras said:

I hear everything from "most of the beneficial bacteria is in the filter and there's very little in the rest of the tank" to "there is very little beneficial bacteria in the filter and most of it is in the tank." Honestly I imagine it varies a lot depending on the tank, filtration, and substrate, which would explain why there's such a wide range of opinions. 

I only have sponges in the tank so would it be in the filter or in the tank...🤣

[Griznatch]

 I rinse mine in tank water, mostly because all my tanks have shrimp. The babies love to hang out in my filer media. I don't want them going down the sink or getting shocked from my tap which has gone through a water softener. My outside taps are straight from the well but that water is super cold.
 

Forgot to add I rarely clean my filter media or pre-filter sponges unless it restricts water flow.

Edited September 17, 2021 by Griznatch
add more

[lefty o]

substrate, filter, on surfaces inside the aquarium is where the bb live. it stands to reason that if your tap water has chlorine and ammonia and you rinse your filter in the tap water you will kill off some or all of the bb in that filter. so long as you dont otherwise have an absolutely bare tank, its probably not going to crash the bb colony. if you have a highly stocked tank bare with nothing else in it, you probably would not be wise to risk it. if your tank has many surfaces for bb to live on, killing off even 100% of the bb in your sponge filter will probably do little to no harm in the day or three it takes for the bb to recolonize the filter. one thing in this hobby is that there are few absolutes.

[Patrick_G]

My antidotal evidence: 

I have one unfiltered planted tank that stays stable so there must be some bacteria in there somewhere. 
I also have a 100 gallon Goldfish pond with no substrate and a small box filter with some gravel as media. I’m not exactly sure why it stays stable but I suspect it has a lot to do with the fact that I never clean the surfaces and they’re probably covered with BB. 
 

On 9/17/2021 at 11:46 AM, lefty o said:

substrate, filter, on surfaces inside the aquarium is where the bb live. it stands to reason that if your tap water has chlorine and ammonia and you rinse your filter in the tap water you will kill off some or all of the bb in that filter. so long as you dont otherwise have an absolutely bare tank, its probably not going to crash the bb colony. if you have a highly stocked tank bare with nothing else in it, you probably would not be wise to risk it. if your tank has many surfaces for bb to live on, killing off even 100% of the bb in your sponge filter will probably do little to no harm in the day or three it takes for the bb to recolonize the filter. one thing in this hobby is that there are few absolutes.

Wise words! This should be pinned! 

[Tihshho]

I rinse all of my sponges in tap water. I always have done it and always will. 

[JettsPapa]

On 9/17/2021 at 1:55 PM, Patrick_G said:

My antidotal evidence: 

I have one unfiltered planted tank that stays stable so there must be some bacteria in there somewhere. 
I also have a 100 gallon Goldfish pond with no substrate and a small box filter with some gravel as media. I’m not exactly sure why it stays stable but I suspect it has a lot to do with the fact that I never clean the surfaces and they’re probably covered with BB. 
 

Wise words! This should be pinned! 

I also have a planted tank that doesn't have a filter or air circulation.  I agree that there's bacteria on the tank walls, substrate, and plants, but the plants also do some of the work of the bacteria.

[Struggle]

On 9/17/2021 at 2:17 PM, Tihshho said:

I rinse all of my sponges in tap water. I always have done it and always will. 

I do as well and go so far as to wash the large ones out by putting them on my concrete driveway and blasting them with the hose.

[Colu]

It all depends on what in your tap water if you have high levels of chorine that will kill your benefial bacterial 

[mynameisnobody]

I would think that it depends on what’s coming out of the tap. I would definitely test my tap water before doing so. With that said, any day I’m cleaning any sponge is a water change day or maintenance day, so I just use tank water for cleaning anything in the aquarium. Risk/rewards: risk is you kill some, most, or all of the bb. Reward is you saved a few minutes doing so using tap water. Doesn’t compute for me so I’ll always use tank water for cleanings. 

[Scott P.]

I just want to add, I usually rinse my media in tank water. That said it is fairly obvious that most folks are not watching the video. Jason provides scientific research showing that a quick rinse in tap water kills a very small percentage of the bacteria. You have to really get after it to kill a majority of the bacteria.

[tnnlynch]

I currently rinse my filters in the tank water after I gravel vacuum as the sink is up a flight of stairs. After I pop the filter back in the tank, I toss the water in the yard.  Saves me time though I probably could use the extra exercise. 

[Streetwise]

With the new multi test strips, I have realized that my chlorine is undetectable, so I don’t even bother with off-gassing, and I stopped with conditioners a while back. I wouldn’t have any problems rinsing in tap water. However, my snails, shrimp, and grazers clean my sponges for me, so I haven’t cleaned any of mine yet.

I do squeeze out HoB sponges in a bucket so I can optionally save the mulm, and check for hitchhikers.

[Jeff]

Tap water may not hurt; but why even do it, when you can rinse in tank water?

Rinsing in tap water to me, is a wasted step. 

[Beardedbillygoat1975]

If I’m using the media for mechanical only I see no harm in rinsing in tap. If it’s the only filtration in a tank I won’t do that. It helps to have some redundancy in terms of filtration so you can really clean sponges and things. I sometimes feel cleaning the media for my mechanical filtration does a lot for a tank. Example clean mechanical media, nice water change, good temps and bang there can be breeding and babies.

[Ken]

On 9/17/2021 at 2:48 PM, Streetwise said:

With the new multi test strips, I have realized that my chlorine is undetectable, so I don’t even bother with off-gassing, and I stopped with conditioners a while back. I wouldn’t have any problems rinsing in tap water. However, my snails, shrimp, and grazers clean my sponges for me, so I haven’t cleaned any of mine yet.

I do squeeze out HoB sponges in a bucket so I can optionally save the mulm, and check for hitchhikers.

Thanks for posting that, I had never checked my tap water for chlorine. When you said that I ran and got my shiny new test strips out and my chlorine isn't detectable either. I would think an occasional retest would be a good plan though. I'm glad that giant refill bottle of Fritz has a shelf life through July 2023.

[Keeg]

I live on a well so I only rinse under the tap when im trying to clean a cartridge and I want it cleaned thoroughly with super hot water. Everything else gets squeezed/ rinsed in the nasty bucket of old water to save water. 

[Streetwise]

@Ken, @Keeg, I grew up with perfect well water, so I could get away with 100% water changes before I knew any better. It is nice knowing that your water is safe.