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Mildew smell in my FX5, is it still safe?

1098 Views 10 Replies 4 Participants Last post by  CanuckGame
Hey everyone, so i bought an FX5 used online, and bought all new filter sponges.

after i bought it i decided to give it a test run, so i put all the sponges in it, and put the intake/outtake on a bucket and ran it for a bit to see if it was still in good working condition.

anyways i guess im a dumbass and after i drained it i put it away for a month or two with the lid on. Im now about to set up my 75G tank, i opened the canister and i guess there was still an inch of water in it, and the sponges were still wet..

i didnt use my head clearly, the sponges REEKED like mildew, so i washed everything out and cleaned it all up, the sponges dont smell nearly as bad, but still have a faint mildew smell

are these still safe to use? i sure hope so as they are crazy expensive. im just about to start cycling my tank today so i hope i can still go ahead with this.

thanks for any advice.
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Anytime you buy used equipment you need to sterilize it, the way I do it is to ad a 80% white vinegar 20% extremely hot water(not boiling but around 180-190 degrees) blend and use that. To clean a filter you can simply fill the filter up with the mixture and a bucket, and then put the intake and outflow into the bucket and run it for a while, I usually let it run for 30 minutes to an hour but I like to overdo things, probably 10-15 minutes would work.
Since you have niot started the cycle process yet, I would do the tank, filter and all for a good cleaning. I never fullty trust what somebody else may have done to used tanks so I set up the filter and all equipment and bleach them all together. Half cup of bleah is plenty for a 55. When it has run for a day or so, I drain and change out the water. Any chlorine from the bleach will get diluted if it has not already gassed off. Then you can start out knowing that there are no little secrets like left over oil or pesticide residue or such.
Using vinegar to sterilize is not too effective. Old vinegar will spoil due to the bacteria growing in it.
You can also do a bleach cleaning of the filter equipment and foam. Simply set up the canister to pull from and empty into a bucket of bleach-water (about 10% solution), and run that for 20 minutes or so. Dump the bleach water and run the canister with a few buckets of tap water until bleach smell disapates. Then dismantle the hoses, etc., leave the filter open and air out all components until any moisture evaporates. (If you like, you treat the tap water with Prime to help remove the bleach, but it's not necessary with enough rinsing and *complete* air-drying.)


I guess Rich and I were posting about the same time. Pretty much two ways to do the same thing. :)
Hey guys thanks for the replies. Ive had the filter for about 7 months and did a full clean when I got it.

im not using ANY of the media I got with it everything is new. Im just worried about the mildew smell on the sponges from when I gave it a test run

is there anything harmful with mildew? I already washed the sponges out thoroughly but theres still the faint smell of mildew.

Should I just go ahead with the cycle? Or should I buy new sponges for the filter? II'd rather not use bleach.
I would replace the sponges. If you can smell mildew, there are probably spores, etc. and, which I don't *know* that it would harm the tank, I wouldn't risk it. But, then again, I would completely clean the filter, hoses, etc. -- anything that was left hooked together when you last store it and the mildew problem developed. So replacing the media/sponges would be the least of my concerns.

It's really up to you, how much bother you want to go thru versus what you're willing to risk.
So if I do the bleach clean. I should be good? Ive done alot of reading and it seems like the way to go..

So should I hook the fx5 up to a 5 gallon bucket with say 1/3 a cup of bleach, let it run 24 hours, then let it run in a bucket of fresh water with dechlorinator and keep changing the water in the bucket several times. And then let everything dry out 100?

Im getting 700 dollars worth of Discus once my tank is cycled thats why sketched out about the mildew and now having to use bleach to clean it... yikes...
When I have soft media, I do a lighter bleach than for hard stuff. Remember what pouring bleach straight on you pants will do? I try not to do that to my soft media!
In a five gallon, I might look more toward a couple tablespoons to aviod damage to the sponges, etc. In your drinking water it runs from 3PPM up to a limit of 10PPM but how to calculate that is not in my book.
For being sure it is cleared, there are several big items to keep in mind. one is rinsing it when done. That reduces the PPM. Second is drying. The chlorine is a gas and will leave when dry. That's why we smell it around a pool. The chlorine gas is blowing away. Totally dry is totally gone. The only difference is the bleach water soak is higher PPM than drinking water. We never want to sterile our stomach! But then when we rinse things, that takes the PPM reading down to low levels.
But if still concerned, we can still deal with it just like we do in our tap water. A touch of dechlor gets the chlorine out of tap water so it does the same for the bleach we have used.
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ok, so i did the 24 hour run with bleach, and now im doing the run with fresh water with dechlorinator in it switching out the water every 4 hours with fresh water.

when i emptied the FX5 with the bleach water i noticed all the sponges had turned yellow? they were all brand new bright white, now their yellow? haha is this normal? the sponges feel the same as they did when i first put them in, just the color has changed.
Not sure why they would turn yellow as we normally use bleach to get things white. Some reaction with the sponge material but Have no idea what unless there was a lot of algae or such which is now dead.
No Algae the sponges were new never used haha
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