What Size Gray Water Tank???

[coairstream]

I have a 1972 25ft Trade Wind that does not have a gray water tank. Im remodeling it and figure I'll go ahead and install one. I need to replace a few beams underneath and thought about relocating them but after more thought and good Advice from Andy I decided not to mess with the structure. So this is my question...

The fresh water tank I believe is 50 gallons and has its factory way of being installed and secured. I need to work around the beams behind the axel going towards the back for the gray water tank. I know your gray water tank should be a bit larger than the fresh for soap etc. but I just don’t see how to make it work with the beams. How small can I go without being to small? Should I get two made drill a hole in one of the beams and daisy link them together or would one between two beams be fine as big as I can get it? I really don’t have to have a gray water tank, but for resale and the fact that I have it exposed I feel I should do it.

Thank you

[Boondocker]

Cody,

I recently added a 25 gallon gray to my 68. The fresh water tank in mine is closer to 30 gallon. Figure at least five gallons will end up in the black tank and that much more will be "eliminated" elsewhere. The thing to do is to pull the belly pan in the area you want to put the tank and measure the space available. Make sure and note anything that may become an obstruction. Then you have to decide how tall of a tank you can live with. Mine goes below the belly pan, but stops at the height of the axles. Because it is behind the rear axle it is reasonable protected (I hope). I suppose you could link two tanks to get larger capacity if you really wanted.

[RLS]

Our fresh water holds 54 gallons and the gray holds 39. From our experience, the gray always fills up fast.

[Minno]

Hi Cody,

I think the size of the gray water tank is more a personal preference than anything else. Having said that, I personally would go for as large a tank, or a pair of tanks that you can afford and fit into the frame. I plan on installing a pair of tanks in the two frame openings that are directly above and directly behind the rear axel of Little Girl. My frame openings are 22.5” x 58”, and the frame is 5 inches tall. I have just over 6 inches from the bottom of the plywood floor to the top of the axel, so that pretty much defines the max dimensions of the tank in that opening. The second tank could be a tad taller than 6 inches, but I’ll probably get two tanks the same size. The problem you’ll find is finding tanks that fit, especially if you want to maintain the entire integrity of the belly pan. If you’re willing to have a tank stick below the belly pan, that opens a few more possibilities.

Regarding daisy chaining two tanks together, if you’re going to connect the outlets together with a “Y” fitting before the drain valve, then you have in effect daisy chained them together, and you don’t need to drill through the frame. Don’t forget each tank requires a vent.

Chris

[Aage]

1974 was the first year for gray tanks. In the 31' Sovereign, they put in a whopping 10-gallon one.

Somebody in the design department had a good sense of humour!

[Boondocker]

Small gray tanks are good, they encourage conservation. If you boondock a smaller tank forces better habits. Two people ought to be able to go 4 days if not 5 on a 30 gallon fresh and a 25 gallon gray tank.

[DreamStreamr]

Our 2005 International has 39 gal each for fresh and gray, and 18 for black. If boondocking we have to do as Rodney says and be really conservative with wash and rinse to keep from filling the gray tank too quickly.

I read about one guy who retrofitted a pump between his gray and black tanks to transfer from gray to black (but his black tank wasn't half the size of the others like ours is). Pretty clever idea if you have a larger black tank than you need, lets you manually equalize between them according to current conditions.

We catch rinse water in a bucket and save it for manually flushing. This saves us twice -- instead of using potable water in the toilet we are re-using rinse water. And instead of adding the rinse water, after only one use, to the gray tank we are putting it into the black tank.

Although our black tank is only 18 or 19 gallons, the twice larger gray tank was still filling first until we figured out how to work the system. Again as Rodney stated, we can generally go a week or a little more with our somewhat small gray and black holding tanks.

And we could go even longer if we needed to. We haven't yet needed to resort to just sponge baths to economize on fresh water usage or holding tank space.

Jim

[Boondocker]

Originally Posted by DreamStreamr

Our 2005 International has 39 gal each for fresh and gray, and 18 for black. ............

..... our black tank is only 18 or 19 gallons....
Jim

Jim, those tanks are massive. Well, not the fresh, but the gray and black... well I couldn't fill up a 19 gallon black tank in a month.

[DaveFL]

Originally Posted by Aage

1974 was the first year for gray tanks. In the 31' Sovereign, they put in a whopping 10-gallon one.

Somebody in the design department had a good sense of humour!

We had a 15 gal in Van camper and it was good for rinsing pipes after dumping Black. Van had the easiest dump setup and no shower, our AS has twice the capacity but fills rapidly due to showers and dishes. I would install the largest possible as it can be dumped before travel.

[firedog]

I will pulling a 500 gal. honey wagon behind my 29 excella classic.TO much bull- - in a my old club,.their in need a big ENEMA.

[DreamStreamr]

No Rodney, not so huge -- the tanks are our limiting factor in boondocking. Something has to be the limit, right?

Took care of the power with two 125w pv panels and a pair of golf cart batteries, plus a sweet little 1kw generator. Carry enough food and alchohol for 14+ days. Don't want to wash clothes too often, it just wears them out.

So our limiting factor is pretty squarely on the black tank, for now. Unless we aren't at the RV and just use other facilities. Then the fresh water runs out before the tanks fill.

Not too bad a problem -- at a gallon per day per person (FEMA's minimum rec) we could go 20 days without any other sources. And, with enough beer, we could extend to twice this!

Jim