Clack ws1 AIO filter help

[Lefebvres090428]

I have acquired a tank and older fleck softener head. I would like to turn the tank into a iron/sulfide AIO filter. Tank size is 10x40. When looking for a used head which ones are good for AIO? I have heard fleck 2510, clack ws1. With these heads is there any way to tell if it is configured for a softener or filter? Is it difficult to modify to a AIO system if I end up with one that was a softener head previously? Thinking I am going with a katalox lite system.

 

[Reach4]

With these heads is there any way to tell if it is configured for a softener or filter? A valve sold as a filter will not have metering. There can be other difference that go along, including the programming. Maybe the piston. Maybe more.

I am no help in trying to convert to AIO.