I have a fouled softener that I want to clean and disinfect the resin bed in.
The unit has a Fleck 2510 control head and a 9" diameter tank that is supposed to have 1 cubic ft. of resin in it.
The unit is about 3 years old.
I have the tank contents in 5 gal. buckets and have used some Res Up to begin cleaning the resin.

Questions:

What should the resin look like when clean?

Right now it looks sort of like salt and pepper; should it all have an amber color when the iron is cleaned off?

Can the resin be damaged from too much cleaning?

What can I use for disinfectant?

I have Iron Out and Res Up but they don't appear to be disinfectants.

Could PineSol be used or would it damage the resin?

The tank was about 3/4 full of resin/gravel which seems to be a lot more volume than a cubic ft. of resin + gravel would create.

Is that normal or was the tank overfilled with filter media?

Thanks for any replies!