Plumbing for Saltwater Mixing Station

cmcimino · Jan 22, 2019

So I picked up two 35 gallon water storage containers this weekend for 50 bucks each and want to make a mixing station in my garage where I can pump salt water to my tank for water changes. Right now my RODI is installed under a bathroom sink in the guest bathroom, but I would like to move it to the garage with the mixing station. Luckily my house had a water softener installed at some point (was disconnected when I bought it the house) so I have some existing plumbing connections to work with, and a drain! See below.

I am assuming what is there now is PEX pipe, it's fairly rigid, not like a standard hose. I plan on cutting it at the wall and providing elbows so that the new plumbing runs flush to the wall. My question is, what should I plumb with? I feel like PVC is going to be the easiest for me. I can provide a tee with a 1/4" threaded connection to connect my RODI filter to. I also plan on putting an emergency shutoff valve on the pipe too. See diagram below.

Open to any suggestions! Thanks

Big G · Jan 22, 2019

Plan looks good. I have a similar setup in my garage. Makes water changes so easy. You are going to love having RODI on hand and ready to go as needed.

cmcimino · Jan 22, 2019

Big G said:
Plan looks good. I have a similar setup in my garage. Makes water changes so easy. You are going to love having RODI on hand and ready to go as needed.

Absolutely. Picked up a big external pump so I can pump my water directly to the tank! No more mixing individual buckets.

DLHDesign · Jan 22, 2019

Agreed; looks like a solid plan.
Note that working with PEX requires special tools to crimp the bands - often a tool that can run around $50+ or so at a big-box tool shop. You might want to see if there's a local plumbing supply store or the like that could rent you one instead, if you don't already have one.

Big G · Jan 22, 2019

cmcimino said:
Absolutely. Picked up a big external pump so I can pump my water directly to the tank! No more mixing individual buckets.

cmcimino · Jan 22, 2019

DLHDesign said:
Agreed; looks like a solid plan.
Note that working with PEX requires special tools to crimp the bands - often a tool that can run around $50+ or so at a big-box tool shop. You might want to see if there's a local plumbing supply store or the like that could rent you one instead, if you don't already have one.

I was able to find a shark bite coupling to connect PVC to PEX.

https://www.amazon.com/SharkBite-Fi...d=1548186415&sr=1-4&keywords=sharkbite+to+pvc

A little iffy on it, but it has good reviews.

DLHDesign · Jan 22, 2019

Shark Bite is good, but I wouldn't use it inside wall. Should be good for your need here, however.

They also have Shark Bite valves and T's, which might be of use for your need here.

cmcimino · Jan 22, 2019

I think I have a final diagram of how I am going to plumb everything. I have decided to make it so I can fill either tank with RODI water by closing and opening valves in the RODI water lines. I also included a tee fitting with a hose going to the drain so I can flush my RO membrane after each use and not have to worry about any contaminated water getting in my containers. I can fill up a bucket of RODI water by simply opening the water valve and letting gravity do its work. The salt water container will be plumbed to an external pump where it can recirculated water when mixing salt. I am also going to put another uniseal on the container to run a heater through. When I want to do a water change, I will simply close the top valve and open the other. I'll connect a hose to this some sort of valve to fill the tank. Any one see any flaws in this? I am open to suggestions.

Big G · Jan 22, 2019

Yep! Looks good. Very similar to mine:

DLHDesign · Jan 22, 2019

One thing that your design may not easily allow for is moving RO/DI water into your salt tank. You could do it manually, I suppose, but with the same equipment (less, really), you could have that ability as well. Using @Big G's setup above as an example; the pump is connected to both the RO/DO and salt tank, with a T-junction and ball valves to open/close each tank. In this setup, the pump can be used to move water both from the RO/DI tank into the salt tank as well as to circulate the salt tank itself. You can also (with the addition of the additional ball valve above the pump as above) use the pump to pump out both RO/DI and salt water - which may save you from having to lug buckets around, perhaps. With this setup, the RO/DI line only needs to go into the single RO/DI tank.

cmcimino · Jan 22, 2019

I plan on running RO line to both tanks and controlling the direction of flow by using valves in the RO water piping. Each can be filled separately that way I don’t have to pump the water from the RO tank to the saltwater tank. The pump will just be used for mixing and outputting to the display tank.

homer1475 · Jan 23, 2019

Plan on adding a float valve to each tank? With putting the RO/DI in each barrel, you will have to add a float to each tank to shutoff the RO/DI when they are full.

Most of us just fill one barrel with RO/DI, then use a pump to pump water into the other mixing barrel. You can of course do it anyway you want, just be aware you will need 2 float valves. One for each tank if you go forward with the way you want to plumb them.

cmcimino · Jan 23, 2019

homer1475 said:
Plan on adding a float valve to each tank? With putting the RO/DI in each barrel, you will have to add a float to each tank to shutoff the RO/DI when they are full.

Most of us just fill one barrel with RO/DI, then use a pump to pump water into the other mixing barrel. You can of course do it anyway you want, just be aware you will need 2 float valves. One for each tank if you go forward with the way you want to plumb them.

Valid point! I ordered two float valves, my luck I'd flood my garage.