Parallel Katalox Filter Trouble

[Althea Later]

My iron level fluctuates with the seasons currently it is 3.5 with maganese level of 0.134. It has been as high as 6 during the dry season.

I have 2 -12in x 54 in AIO Katalox filters plumbed in a parallel configuration with Fleck 2510. About 4 cubic ft of Katalox

I'm having to backwash both tanks nightly otherwise I get iron bleed through after showering

I noticed that when filter #1 is backwashing. I can hear water running through the filter #2. If I close the isolation valve for filter #1 the water flow slows going into filter #2. The drain line for both tanks is shared.

Is it possible that the discharge/ backwash from filter #1 is backing up into filter #2?

It would explain why the filters are struggling to keep up with the iron.

Current settings are BW 14 minutes, Air draw/ slow rinse=40, rapid rinse=6 minutes

Thanks in advance

 

[Bannerman]

You didn't specify how old the system is. It's possible that one or both of the 2510 control valves require rebuilding with new spacers, seals, O-rings, and possibly new pistons. These are common wear items that normally require replacement, usually after several years of constant use.

Although rebuilding one/both valves may be needed, there are other possible causes for the iron leakage and noise, which should be first considered.

The purpose of a Rapid Rinse cycle, is to recompact the media bed after it was loosened and expanded during the earlier backwash cycle.

Because your system is AIO, to ensure there will be as much air as possible remaining in each tank, it would be best not to utilize a Rapid Rinse cycle. The rapid flowing water maybe causing a substantial amount of the not yet compacted air within each tank, to become pushed out to drain. Even with no RR cycle programmed, since service flow to fixtures will be downward through the media, the media will become progressively recompacted whenever water flow to fixtures is occuring.

The noise heard from the alternate tank, maybe being caused by pulsating air/water mixture exiting during the RR cycle, flowing up into the drain line leading from the alternate control valve.

Once the drain valve closes and service flow is restored, the air within each tank will be compressed into a smaller bubble, equal to the water supply pressure. The air bubble will be compressed into the top half of each tank.

The raw water entering through each control valve, will pass through the air bubble before coming into contact with the KL media below. Oxygen in the air is utilized to assist the KL media by initiating the oxidation of ferrous iron and ferrous manganese, which is then further catalyzed in the upper section of KL media. It is the oxidation/catalyzation process which causes a conversion of ferrous iron/manganese to a ferric state. Once oxydized, the resulting ferric solids can then be filtered out by the remaining KL media in the lower section. The accumulated solids are flushed to drain during each BW cycle.

If there is insufficient air remaining in each tank following the RR cycle, then maybe not all of your substantial 3.5+ ppm iron + 0.134 ppm manganese maybe being fully oxydized/catalyzed within the upper section of each tank, resulting in the KL media becoming over saturated and causing the media capacity to become prematurely depleted.

Another possibility for noise and loss of air, is a lack of check valves placed in the supply line, just prior to the inlet connections to each control valve. Since the tank undergoing regeneration will be at lower pressure than the alternate tank, without indiviual check valves to prevent backflow between tanks, the compressed air in the alternate tank may exit backward through the supply inlet, flowing into the lower pressure tank undergoing regeneration. Of course, any air exiting from either tank, will result in water entering to replace the lost air.

 

[Sponsor]

 

[Althea Later]

Thank you, I believe you may have nailed it in the last paragraph. No check valves.

The Katalox is new. The heads are old 20+years and RR can not be eliminated. 6 minutes is the magic number for RR because the discharge during RR blushes heavily with remaining iron and doesn't clear after 4 minutes RR. My water comes from a shallow well to a cistern and is heavily oxidized already. There is definitely air remaining in system after RR and before the next regen. The water to the house is milky with air bubbles.

Do you think it is worth upgrading to the 2510sxt to be able to remove RR? The filter is cleaning itself with high iron water. If it's using 60 gallons of water for RR that is putting a significant amount of iron back into the tanks and reducing the capacity