Rotten egg smell after Katalox filter, please help

[Scottmedic]

Hello,
I have been searching for an answer to my problem: I am on well water and i switched from a chlorine injection system with a 120gallon holding tank and a 1.5cuft carbon filter, and a softener to…. a Katalox 1.5cuft media in a 12x52 tank with Ozone, to the carbon filter then softener. I have iron and hydrogen sulfide (rotten egg smell) in my well water and the previous chlorine system worked well but was a huge pain on the ass to maintain and the pump was on need of replacement. I wanted to go with a chemical free system so i went with the Katalox with ozone. The iron being removed and the water appears clear, the rotten egg smell still exists. It is mainly on the cold water side and the five minutes of use in the morning there is no smell. This rules out the hot water heater and leads me to believe there is not enough contact time with the katalox media/ozone to remove all the sulfide smell. The carbon in my carbon filter is 6 years old and i can replace it or change it to a different media but wanted to get expert opinions first. The katalox is backwashing every other day at 10gpm per the manufactures instructions. This issue started from day one of the install and remains the same. Any help or greatly appreciated. I also want to know the best media for hydrogen sulfide removal. Thanks you all.

 

[Reach4]

Well sanitizing may help, but I don't know for how long. https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my well sanitizing write-up.

Since this started on day 1, I doubt that is a problem with backwash... but I will comment anyway.

10 GPM may be a little light with warm water. 30C is 86F.

But can you be sure the 10 gpm actually happens? What pressure does your pressure gauge drop to during backwash?

A way to measure backwash rate is to time how long the backwash drainage takes to fill a 5 gallon bucket. If it takes S seconds, the gpm is 300/S

That table came from data in the second image of https://terrylove.com/forums/index.php?threads/katalox-light-backwash-rate.65066/ The graph is still available on page 3 of https://www.watchwater.de/wp-content/uploads/2019/01/KL_Brochure_NEW_ver_1.1.pdf

I also find this: https://www.watchwater.de/pdf/katalox-light/KL_FAQ.pdf Their literature used to suggest injecting some oxidants, but not now.

 

[Sponsor]

 

[Scottmedic]

Well sanitizing may help, but I don't know for how long. https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my well sanitizing write-up.

Since this started on day 1, I doubt that is a problem with backwash... but I will comment anyway.

10 GPM may be a little light with warm water. 30C is 86F.

But can you be sure the 10 gpm actually happens? What pressure does your pressure gauge drop to during backwash?

A way to measure backwash rate is to time how long the backwash drainage takes to fill a 5 gallon bucket. If it takes S seconds, the gpm is 300/S

That table came from data in the second image of https://terrylove.com/forums/index.php?threads/katalox-light-backwash-rate.65066/ The graph is still available on page 3 of https://www.watchwater.de/wp-content/uploads/2019/01/KL_Brochure_NEW_ver_1.1.pdf

I also find this: https://www.watchwater.de/pdf/katalox-light/KL_FAQ.pdf Their literature used to suggest injecting some oxidants, but not now.

Thank you for the reply, I checked the rate of backwash and it is almost right on 10gpm. Your point about the warmer water and backwash rate is noted so I’ve ordered a 15gmp dlfc, with all I’ve read katalox must be backwashed appropriately to function as intended. Do you know the ideal bed expansion? Does it matter if I have a 2cuft tank (12”) with only 1.5 cuft of media with a gravel bed? I’m going to clean my softener as well and Renee the carbon filter that is 7 years old as well. Thanks for the info, it is greatly appreciated.

 

[Reach4]

If your tank is unpainted, you can shine a light thru while backflushing in the dark. I tend to think bed expansion of 25% or more is desirable, but that is a very non-expert opinion. 50% bed expansion means all of the way, because the normal fill is 2/3 full.

What you really don't want is to have some sections cement themselves to each other.

The required backwash gpm is a function of the cross sectional area.

Many pumps and plumbing systems cannot maintain 10 gpm after the pressure tank is empty.

If your system is outdoors, all plastic needs UV protection. If the tank is unpainted, that includes the tank.

 

[Scottmedic]

I have a 12x52 tank with only 1.5cuft of media and some gravel base, I’m not sure how to figure out the exact required backwash flow/ desired expansion based on that tank size, only 1.5cuft of media, 30c water temp. I have a black tank that light does not penetrate well at all so I can’t see the expansion.

 

[Reach4]

I think the backwash gpm would be the same for a 12 inch tank, whether it has 1.5 or 2 cuft of media.

The extra freeboard will give more margin as to how much flow you can have without blowing media out.

I suspect you have a submersible pump since you are able to develop the high gpm. Even if you have a jet pump, I think you could adapt my sanitizing procedure. You could pull the vent fitting, and make something to recirculate into that hole.

 

[Scottmedic]

I think the backwash gpm would be the same for a 12 inch tank, whether it has 1.5 or 2 cuft of media.

The extra freeboard will give more margin as to how much flow you can have without blowing media out.

I suspect you have a submersible pump since you are able to develop the high gpm. Even if you have a jet pump, I think you could adapt my sanitizing procedure. You could pull the vent fitting, and make something to recirculate into that hole.

 

[Scottmedic]

I do have a submersible well pump, what vent fitting are you referring to?

 

[Reach4]

I do have a submersible well pump, what vent fitting are you referring to?

In the south, there is normally something called a well seal (rather than a well cap). That will have a water pipe penetrating, and going to the pressure switch and pressure tank. There will be the wire penetration. There will also be a vent, and that often has a thing made for the purpose -- pass air, and block insects. Well seals do not usually seal all that completely, so that should be above water, even in wet times.

In colder areas, there will be a pitless adapter below the frost line. In that case, you would have what is called a well cap. With a well cap, you can lift that, and recirculation is easier.

 

[Scottmedic]

Got it, thanks