Mixing station help

[MTsquared]

Mixing station is setup and running as I would like using two brute trash cans. The issue I am having is on the salt side where there is some residual water that doesn’t get sucked out from the pump and ultimately stays in the barrel. This causes a pretty horrific smell as the water is just sitting there stagnant between WC. I just added a tee (see pictures) with a ball valve to hope that it would allow the remaking water to drain out easily and this leaving the bin empty. I also changed the configuration inside the barrel from just a 90 elbow with a little pvc piece on the bottom to a 90 and a 45 (the 45 is basically touching the bottom of the bin). That is not the case so far. I’m thinking maybe since the bulkhead is slightly higher than the bottom of the bin this is the issue? Outside of sticking another pump in there to drain out the residual salt water is there anything I can do to have gravity help completely drain the bin?
Want to get this cleaned out and functioning for a WC. Any input is appreciated and I can provide additional pictures if needed.

 

[blaxsun]

What about some kind of circulation pump in the bin?

 

[mike550]

What happens if you drain the bin if the water line is above the 90? I’m wondering if you could create a natural siphon to get closer to the bottom.

But to your point I always have a bit of standing water between the bottom edge of the bulkhead and the bottom of the bin. I used unions where the pipes connect to the bin so I just disconnect and drain it.

 

[JNalley]

Step 1: Either buy, or have someone weld you a platform with an open center for the trashcan, something like this:

Step 2: Get new trashcan and instead of plumbing the side, plumb the bottom with a valve.
Step 3: I think you can see where I'm going

One of these may also help, but to be fair, you'll never get 100% of the water out of the bottom with just a pump
https://us.sicce.com/en/products/solid-handlings-utility-pumps/ultra-zero.html

 

[MTsquared]

Step 1: Either buy, or have someone weld you a platform with an open center for the trashcan, something like this:

Step 2: Get new trashcan and instead of plumbing the side, plumb the bottom with a valve.
Step 3: I think you can see where I'm going

One of these may also help, but to be fair, you'll never get 100% of the water out of the bottom with just a pump
https://us.sicce.com/en/products/solid-handlings-utility-pumps/ultra-zero.html

Good idea I think this is ultimately the only decision to drain 100%. On my last WC with the change in the configuration in the elbow inside it did drain most of it and then I just wiped out the remaining with a towel and allowed to air dry.