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Old 03-17-2015, 01:52 PM   #11
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Originally Posted by SULTINI View Post
Really don't want to cross connect the gray and black. Keep two separate systems. GOD forbid somehow a cross connect and blocked black tank sewage will flow up into the shower, sinks etc.
Right. That would be another issue.


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Old 03-17-2015, 02:04 PM   #12
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Originally Posted by chriscowles View Post
I do something like that by opening the gray valve after the black tank is empty but only if the gray tank is relatively full, to reduce the likelihood of backwash.
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Old 03-17-2015, 04:16 PM   #13
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I have 2 gray tanks. 50 gal each, 1 is kitchen, 1 is Bath/shower. Bath tank fills in a couple days, kitchen in a couple weeks (we use a small tub to wash dishes and dump it outside cause we dont want food remnants in our linescthat would build up or attract bugs). Read somewhere to keep dump cap on and open both greys so theycwould level out. Tried it once and what happened was both greys emptied and leaked over into the closed black tank which immediately showed full. No nasties because we werent using the black yet. I may have a black valve leak on this new 5er.
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Old 04-01-2015, 08:22 PM   #14
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RV Grey Water Potty Flush | ModMyRV

I'm thinking this might be the mod the original poster was talking about. Cool idea, but a bit more work than I'm willing to do. The bucket method will continue for me.
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Old 04-01-2015, 10:26 PM   #15
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I did see that and agree it's overkill but was referring to this thread on this FR site. The reference was vague, which is why I asked. It sounded to me like the overflow was passive but would have to be one-way.

I guess I could inquire with the member who posted that comment but I only just found it again.

EDIT: I tried to reply to the thread but it's ancient, and closed. Also, the member (Triguy) hasn't posted a message since August. I sent a PM in the hope that he's still around. Maybe others here will recall that topic and know what he was referring to.

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