Is it OK to install blackwater tank above the toilet discharge outlet?

[EvilRabbit]

Apologies for the confusion:
1) I meant black water dribbling back, not raw water.
2) It's a fresh water, electric head
3) Brand is Vetus TMWP

Concern is that their is some flow back into the head and that we have to flush 2-3 times to completely clear the lines - as they fresh water heads we consume a lot of water then

Originally Posted by EvilRabbit

Getting raw water slowly dribble back into the bowl and having to flush 2-3 times to clear the lines. I assume this is what is in the line between the tank and the discharge outlet of the toilet. Is the issue here is that the holding tank has bee fitted above the discharge and pipe running 90 degrees for half the distance?

[Terra Nova]

It is necessary to flush enough to get the waste out of the hose and dry flush enough to clear the standing water. Although it lengthens the hose slightly, it would help to have a short loop above the holding tank.

[EvilRabbit]

Lowering the tank makes the most sense for me. Going open up and see tomorrow what’s possible. We will replace jokers and also install some inline non-return valves. Will feedback on the results.

Originally Posted by peghall

A brand new joker valve will block backflow, but every flush stretches the slit and "lips"...in a short time (how long depends on how much use the toilet gets you'd be able to see daylight through it, which is enough of a gap to begin to allow very slow seepage...gradually increasing. So you'd have to replace the joker valve as often as every couple of months to prevent backflow completely. But that would create another problem: waste left sitting in the discharge will lead to a stinky hose. In fact, judging from the color of it, I suspect it's already seriously permeated.
8
Relocating the tank is the only good solution. It has to be sitting on something...What's below it? If that won't work, is there any available lower space within 6-8' of the toilet? Or even further...it's better to have a longer discharge hose than what you have. How long is the discharge hose now?

And btw...What's the make/model of your toilet? Does it have a "dry bowl" flush option?

Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

[SailFastTri]

If he's flushing with sea water, flushing to clear the hose will only mean sea creatures will rot in that hose instead of human waste. Either way it has the potential to stink if left to stand for a few days.

[Terra Nova]

Originally Posted by EvilRabbit

...We will...install some inline non-return valves...

Very bad idea. Each one is a potential clog.