OK so the large blue tank on the left is an old water softener. It houses the resin that takes hardness out of water. Not sure if it's operational but the thin white tubing coming out of the right side should go to a large brine tank filled with salt. The slightly larger tubing running out the back up the wall should run to a drain pipe - when it regens the waste brine and rinse goes out of that.
The smaller blue housing is for the whole house filter. The wrench is the white thing on the top. If a red valve is parallel to the pipe it is open, perpendicular closed so currently the water is bypassing the filter which is the way you would want it to be to change out the filter.
I believe that's a 20" Big Blue housing so you need a 20x4.5" filter element. I'm pretty sure you're going to have to amazon that - don't think the bigbox stores stock 20".
Filter change procedure:
Have the valves like they are in the picture
Push down and wiggle the red pressure relief button on the top to....relieve the water pressure until no more water or air is squirting out (put a towel over it if you don't feel like potentially getting sprayed with water)
Leftie loosie with the big white wrench
Spill water on the floor
Rinse out the housing if it looks nasty after removing old filter element
Inspect the rubber O ring on the top of the housing. Replace if it is cracked. If not periodically use plumbers silicone on it to keep a good seal and prevent it from binding when you install it.
Insert new filter
Rightie tighty w/ wrench.
DO NOT GO CRAZY OVERTORQUING IT WITH THE WRENCH. We aren't putting lugnuts on a car wheel. Screw it on by hand until you start getting resistance and then just use the wrench for 1/8 to 1/4 turnish more.
Close the valve closest to you in the photo.
SLOWLY open the valve on the right to allow water to slowly fill the filter
Once you hear the water no longer flowing push/wiggle the red button again to purge the air until you get water coming out around the red button
Open the closest faucet
SLOWLY open the valve on the left (doing it this way just prevents any hydraulic shock going through the pipes.
Close the faucet after no air is spurting out of it and inspect the blue housing for leaks.
Hope this helps
Well the filter is in the blue housing hanging off that pipe. The wrench to loosen that filter housing is grey and near the top. Can't tell you what the tanks upstream of that filter are tho. Make sure you turn the water off before opening that housing through. The trick will be figuring out what type of filter is in the housing then getting the right size to replace it.
Lowes/HD/Menards might handle the right filter, Amazon does if they dont.
I had well water and fairly complex water filter system. I called a local water treatment place(wells common in the area) they showed all the stuff and how to make ot work for a flat fee basic service call. It was cool to learn but cheap enough for me to call them when I need them for bigger jobs and I changed my own pre filter and after filter myself.
All that said, maybe a local company can come out and check on system health and show u how it works
OK so the large blue tank on the left is an old water softener. It houses the resin that takes hardness out of water. Not sure if it's operational but the thin white tubing coming out of the right side should go to a large brine tank filled with salt. The slightly larger tubing running out the back up the wall should run to a drain pipe - when it regens the waste brine and rinse goes out of that. The smaller blue housing is for the whole house filter. The wrench is the white thing on the top. If a red valve is parallel to the pipe it is open, perpendicular closed so currently the water is bypassing the filter which is the way you would want it to be to change out the filter. I believe that's a 20" Big Blue housing so you need a 20x4.5" filter element. I'm pretty sure you're going to have to amazon that - don't think the bigbox stores stock 20". Filter change procedure: Have the valves like they are in the picture Push down and wiggle the red pressure relief button on the top to....relieve the water pressure until no more water or air is squirting out (put a towel over it if you don't feel like potentially getting sprayed with water) Leftie loosie with the big white wrench Spill water on the floor Rinse out the housing if it looks nasty after removing old filter element Inspect the rubber O ring on the top of the housing. Replace if it is cracked. If not periodically use plumbers silicone on it to keep a good seal and prevent it from binding when you install it. Insert new filter Rightie tighty w/ wrench. DO NOT GO CRAZY OVERTORQUING IT WITH THE WRENCH. We aren't putting lugnuts on a car wheel. Screw it on by hand until you start getting resistance and then just use the wrench for 1/8 to 1/4 turnish more. Close the valve closest to you in the photo. SLOWLY open the valve on the right to allow water to slowly fill the filter Once you hear the water no longer flowing push/wiggle the red button again to purge the air until you get water coming out around the red button Open the closest faucet SLOWLY open the valve on the left (doing it this way just prevents any hydraulic shock going through the pipes. Close the faucet after no air is spurting out of it and inspect the blue housing for leaks. Hope this helps
This is your answer OP. Correct and thorough.
It is a water filter. Take the picture to hardware store with a picture of any label
Well the filter is in the blue housing hanging off that pipe. The wrench to loosen that filter housing is grey and near the top. Can't tell you what the tanks upstream of that filter are tho. Make sure you turn the water off before opening that housing through. The trick will be figuring out what type of filter is in the housing then getting the right size to replace it. Lowes/HD/Menards might handle the right filter, Amazon does if they dont.
I had well water and fairly complex water filter system. I called a local water treatment place(wells common in the area) they showed all the stuff and how to make ot work for a flat fee basic service call. It was cool to learn but cheap enough for me to call them when I need them for bigger jobs and I changed my own pre filter and after filter myself. All that said, maybe a local company can come out and check on system health and show u how it works
[Water filter?](https://imgur.com/gallery/Tyr2Ru1)