Emptying grey and black tanks

[Gutz54]

I just read an opinion piece about emptying the black tank and then the grey water tank afterwards which we all do. In this story the writer said that after you empty the black tanks you should shut off the black tank valve before you empty the grey water tank?? I have always left the black tank open when I empty the grey one?? Does it matter ?? and why?? Also do any of you dump some Clorox down your toilet sometimes to help with the smell?? Thanks

[1retired06]

We use Thetford chemical and a cup of pine-sol each time, and that works for us. I do close up both black tanks after dumping and then do the gray. Never thought about it, just my routine. Have never experienced gray water being pushed back to the black tanks, guess that could happen. Do leave our gray tanks open until a day or two before I dump the blacks.

[Camp CA]

Originally Posted by Gutz54

I just read an opinion piece about emptying the black tank and then the grey water tank afterwards which we all do............ do any of you dump some Clorox down your toilet sometimes to help with the smell......

I dump the black tank first with the water flush open. Then close the black tank valve and fill the tank with 10 gallons of water metered through the flow meter, then shut off the flush water, while dumping my gray tanks one by one.

I never put bleach or chlorine down the rv or sailboat toilets. It will almost certainly kill the beneficial bacteria that breakdown the solids and could expose you to tank clogs and foul odors. Suggest using "Happy Campers Organic RV Holding Tank Treatment" and a good water flush prior to and during draining the black tank plus filling your black tank with say 5 - 10 gallons prior to use.

You might find these threads interesting:

https://community.fmca.com/topic/287...he-black-tank/
http://www.rvforum.net/SMF_forum/ind...?topic=34944.0

[Gutz54]

Thanks!!

[DQDick]

We use Happy Camper and don't have an oder problem. Just to confuse you further: If I can use the power flush then I close the black before opening the grey tanks. If I'm at a dump station then I leave it open and use the grey water to flush it further.

[mtlakejim]

Our model has a separate dump line for the black tank and our campsite happened to have two dump lines. So we just leave the gray tanks open all the time and wait till the black tank is burping in toilet to dump while using the OEM tank flush about once per week. Once every couple months I run a spray hose down the toilet for extra strong rinse. Zero issues and we are full time.


We use Thetford for the smell but it is not really an issue for us. I think part of the reason for that is we use a LOT of water when we flush so solids don't build up in the tank.