Softener and filter layout

[imscoop22]

I'm going to be installing a softener and filters for my well water. I have a spin down filter for course sediment and a multi-stage sediment filter for smaller sediment. What I have is more or less what is depicted in the attached picture (came with the spin down filter). I don't have a UV light. I have a few questions about how to set this up vs the diagram.

First, the bypass has two shutoff valves but many of the configurations I've seen have only one. What is the benefit to having a second valve on the bypass?

Second, I want to run a line to my hose bibs before the softener but I'd like it to pass through the spin down filter so any course sediment is removed (I sometimes see what looks like rust particles and fine sand). I'm assuming this is ok? Is there a need to install a shut off valve on this line?

Lastly, I don't understand why the multi-stage filter in this diagram is after the softener. Wouldn't it be best to install it before the softener?

 

[Bannerman]

To fully bypass each device, to allow any device to be removed for service or replacement while allowing the others to continue to function, a 3-valve bypass is recommended for each.

Most softeners utilize a backwash cycle during each regeneration cycle. While a softener is not considered to be a filter, when present, some sediment and debris will commonly become trapped within the upper levels of the resin bed when the softener is softening the water to flow to the home's fixtures. The backwash cycle will cause the resin beads to be loosened and lifted so debris will become released and then backwashed out to drain.

When larger debris particles are observed, removing the larger particles using a coarse filter of sufficient size is recommended before the softener, as a coarse filter will result in less flow restriction which may reduce the flow rate the softener requires to fully backwash the resin bed.

When the water supply is from a private well, since the water entering the softener will not typically contain chlorine, multi-stage cartridge filters will be often installed after the softener to more finely filter only the water that will be actually utilized or consumed by the person's within the home. Depending on the total capacity of the softener, the regeneration cycle will usually consume up to 100 gallons of water that will not benefit from finer filtration, and water flow for regeneration may overwhelm the limited media capacity of a typical small filter cartridge thereby resulting in a flow restriction through the cartridges.

Because Chlorine will damage resin over time, removing the chlorine from the incoming flow to the softener with a large volume of granular activated carbon media within a backwashing filter, is the usual recommended method.

You only mentioned sediment removal which I anticipate will not include a carbon stage. Carbon media does not function as a mechanical filter to remove contaminants, but relies on a process called adsorption which will require the water to have sufficient contact time with the media for adsorption to take place. Depending on the specific contaminants to be removed, the effective flow rate to provide sufficient contact time is between 1 to 3 gallons per minute, per cubic foot of carbon media. As such, the small quantity of carbon media within a typical filter cartridge, will provide limited contaminant removal benefit in a point-of-entry application.

Since you can observe rust particles (ferric iron) in your well water, I suspect the water actually contains ferrous iron (clear iron that is fully dissolved in the water) so the rust is a result of ferrous iron was oxidized and converted to a ferric state.

Has a full lab test been performed on a sample of the raw water directly from the well to identify which contaminants and quantities are present? Always recommended to be performed at least every few years, and particularly before installing new or replacement water treatment equipment.

The basic WaterCheck test offered by National Labs is most often recommended on this forum. National Labs well water test