water tanks

solo318 · 07-07-2016, 01:30 PM

Now that I've already ordered my tanks, I'm having second thoughts about grey and fresh water sizes. I am going to have 42 gallon black and 50 gallon grey and fresh. I spec'd these sizes based on some of the big pusher diesels. But now I'm having second thoughts.
I'm contemplating joining the fresh and grey and adding another 100 gallon fresh.
So my question is. How big are your tanks, and how do you use them. with my current MH we almost never dry camp, but when we do it's always a grey water tank that gets full to quickly.

Bob86ZZ4 · 07-07-2016, 06:33 PM

Mine has 200 gallons fresh, 75 grey, 25 black. I bought it used so had no choice of sizes. I thought that black sounded kind of small. But, I've never come close to filling the black when the grey fills up. I am happy with these sizes. I think my wife and I can go about a week before needing to dump out. And that would be with taking several showers along the way because we jog and bike quite a bit. I like having 200 fresh. I like to fill those (there are 2 100 gallon fresh tanks under the bed) before we leave. I like to use my city water rather than trusting park water on the road. I never hook up to the park water when at a campground. I always like to use the water pump and my fresh water tanks for all household water needs. Much easier to turn off the electric pump when not needing it. I don't trust the plumbing system to not spring a leak and flood the camper with city water pressure. We also never drink the fresh water. Even though I do flush it out once a year and do the bleach treatment. I just buy gallon jugs of drinking water for $0.88 and we use those to drink, and make pasta.

samcrimm · 07-09-2016, 11:47 AM

We have 2 100 gal tanks under the bed too, but only 42 gray and black. When the gray fills up I fill up the black with it...... Takes almost two weeks to fill up the black, we can get 4 showers and daily use out of the gray tank, but sure wish it was bigger. Our trip out to Colorado was only 3 nights total in a campground, the rest of the time we use walmart or a parking lots. We are in Alabama and the rest stops have dump stations.... don't need them this trip but I have used them with my old class c. I also use a filter when I am at the camp grounds, not worried about the water. So I am happy with my set up except for the gray.

Sam

bushpilot · 07-10-2016, 09:59 AM

Ours are 2x 110g fresh (220 total) and 2x 55g black & gray (110 total).
220 gallons seems plenty for fresh (i sure as heck wouldn't want to run out of fresh water).

I (try to) only fill our fresh water tanks from known reliable sources (our house spigot). but we do use the park water when we have it (we just don't drink from it & we generally don't drink from our own tanks....always have bottled water). If were in a park (connected to city water), we turn the water supply off (via 1/4 turn hose/valve) when we leave the coach - just to avoid the chance of a flood from a busted water line or something) while were gone.

I filled the black tank once (occasional use while on my in-laws curb for 6 weeks) - i had a tank sensor wire break and didn't realize the tank was full...didnt have a problem but i would have taken action to drain it sooner.

I too wish the tanks were larger (but for the life of me as i think about it, i don't know why) - we've never filled the gray (or black) even on a long race weekend with several guys taking showers.

The gray tank is the least of our worries, if it gets (near) full, you can always just leach off the gray water into the soil (under the cover of darkness) - after all its just soapy...the trees and grass love it (and the soap can help to minimize bugs).

We're not full-timers & we don't stay in one place very long (unless its my MIL's).
we (mostly) use our coach like a station wagon, long road trips & occasional camping - we've never had a problem finding a dump station at some interstate rest area or camping world (free) & if necessary we could always pay to dump it at pilot/flying j truck stops.

our storage lot has a dump tank (and wash bay) - so we generally just bring home what we have and i dump & wash the tanks before i put it in our garage.

38Chevy454 · 07-11-2016, 06:54 PM

Quote:

Originally Posted by bushpilot

The gray tank is the least of our worries, if it gets (near) full, you can always just leach off the gray water into the soil (under the cover of darkness) - after all its just soapy...the trees and grass love it (and the soap can help to minimize bugs).

The old clandestine grey tank dumping process. I have to admit doing it also

Never have had the black tank get full, but over a longer period the grey tanks get full.

solo318 · 07-12-2016, 08:03 AM

Thanks guys. I am going to putt my 2 existing tanks in parallel and I'll add a 100 gallon tank in the back of the truck fro fresh water. As usual you guys are awesome.

bushpilot · 07-12-2016, 08:44 AM

if black water is in the gray water tank, could there be an odor/vent issue?

won't the odor / gasses in the (dirty) gray tank escape thru the sinks and shower drain? are the p-traps enough?

on a black holding tank it vents thru the roof and toilet is sealed with the valve & water to prevent gasses escaping into the living area.

bushpilot · 07-12-2016, 10:57 AM

heres an interesting configuration - EBAY Showhauler that has the following tank configuration...

150 Gallon Freshwater
72 Gallon Greywater for Rear Bath
72 Gallon Blackwater for Rear Bath
72 Gallon Greywater for Front Bath and Kitchen
72 Gallon Blackwater for Front Bath

the fresh seems a bit small for a bunkhouse.
I'd be more than happy with duel 72 gallon holding tanks.

solo318 · 07-12-2016, 10:58 AM

Sorry for the confusion. I already have 2 50 gallon tanks. for grey and fresh. I'll put those in parallel and add a 100g tank for fresh water.

Mntom · 07-12-2016, 09:13 PM

Quote:

Originally Posted by bushpilot

if black water is in the gray water tank, could there be an odor/vent issue?

won't the odor / gasses in the (dirty) gray tank escape thru the sinks and shower drain? are the p-traps enough?

on a black holding tank it vents thru the roof and toilet is sealed with the valve & water to prevent gasses escaping into the living area.

P-traps are more than enough to stop the odors. If they didn't you would have odors in your house since the black and grey water are in the same pipe and also the traps are the same ones in your RV.

samcrimm · 07-12-2016, 10:00 PM

Quote:

Originally Posted by bushpilot

if black water is in the gray water tank, could there be an odor/vent issue?

won't the odor / gasses in the (dirty) gray tank escape thru the sinks and shower drain? are the p-traps enough?

on a black holding tank it vents thru the roof and toilet is sealed with the valve & water to prevent gasses escaping into the living area.

I don't mix very often, and it not for a week at a time , but I have P traps and I think I have vents for both the gray and the black. So everyone can sleep tonight,,,, no stinky gas in the house.

Sam

RBowman · 07-12-2016, 10:14 PM

I have a total of 5 of us that travel together. 3 teen and pre teen kids and 2 adults. We have 150 fresh and ordered the standard 72 black 72 grey in our showhauler. I'd think about your plans for dry camping vs hook ups. We do both and I regret not having a larger black tank. It's pretty easy to clear out the grey when dry camping and carefully managed 150 gallons of fresh can go a long way, but in situations such as football tailgaiting for 48hrs plus without hookups, the black tank is the limiter. Same is true if we're at a skislope parking area or somewhere like that where we just can't empty the black tank. 200 gallons of fresh may be worth it too. Only other considerations on the black and greys are how those configurations would impact your basement storage if made larger.

bushpilot · 07-13-2016, 01:35 AM

Quote:

Originally Posted by Mntom

P-traps are more than enough to stop the odors. If they didn't you would have odors in your house since the black and grey water are in the same pipe and also the traps are the same ones in your RV.

i understand that but i also don't take my house on a 70mph ride thru the mountains either.

Mntom · 07-13-2016, 08:20 AM

Quote:

Originally Posted by bushpilot

i understand that but i also don't take my house on a 70mph ride thru the mountains either.

I guess I don't see the problem? Have you had odors come from your traps while running 70 mph through the mountains? The only way you would get odors through the p-trap is to plug the vent and pressurize the tank that they are hooked up to. If the traps were dry then you would get odors, but that's the only time.

bushpilot · 07-13-2016, 08:46 AM

Gray water isn't nearly as foul smelling - so any that escapes via the drain would barely be noticeable.

Im really just kinda talking out loud - confirming theres not gonna be an issue.

The water in the p-traps on an rv sloshes around & I'm wondering if that might give odor a chance to escape via a drain.

Theres only 2 ways for a Black tank to vent (primarily thru the roof vent, out of the tank) and thru the bowl. Keeping water in the bowl prevents a seal (like a p-trap).

When i think of a COMBINED tank, I'm thinking they mix and are connected.

I believe a better way would be to (on demand) pump gray water INTO the black tank (when the gray tank gets full).

Mntom · 07-13-2016, 09:33 AM

Quote:

Originally Posted by bushpilot

Gray water isn't nearly as foul smelling - so any that escapes via the drain would barely be noticeable.

That I disagree with. My wife filled the grey tank enough that it started coming up in the tub. Yep, it STINKS.

Quote:

Originally Posted by bushpilot

Im really just kinda talking out loud - confirming theres not gonna be an issue.

The water in the p-traps on an rv sloshes around & I'm wondering if that might give odor a chance to escape via a drain.

If you have an issue with the water sloshing round while you are driving remind me not to ride with you!!

If you look at a trap or better yet have one in your hand with water in it move it around and you will see that if you have water running out of your p-trap you have a lot bigger problems (like you tipped over......)

bushpilot · 07-13-2016, 10:05 AM

Quote:

Originally Posted by Mntom

That I disagree with. My wife filled the grey tank enough that it started coming up in the tub. Yep, it STINKS.

If you have an issue with the water sloshing round while you are driving remind me not to ride with you!!

If you look at a trap or better yet have one in your hand with water in it move it around and you will see that if you have water running out of your p-trap you have a lot bigger problems (like you tipped over......)

man we don't even use deodorizers in either tank anymore - since i installed tank washers.

i get it, its not a race car but I've had stuff come outta the cabinets (on a large bump etc)....so far no tipping over.

i guess I've never expected that the p-traps are completely full of water

samcrimm · 07-13-2016, 01:32 PM

Quote:

Originally Posted by bushpilot

i understand that but i also don't take my house on a 70mph ride thru the mountains either.

I don't drive 70 mph!! Takes too much diesel!

So far no stink....

Sam

bushpilot · 07-13-2016, 05:44 PM

Quote:

Originally Posted by samcrimm

I don't drive 70 mph!! Takes too much diesel!

So far no stink....

Sam

No stink here either Sam...but i wouldnt want BLACK water in my gray tank either.
It makes sense to pump gray water into the black (since the gray fills fastest), but i wouldn't DARE want the risk of blackedned water backing up in to the shower from the drain either.

i set the cruise at 72 (the factory max) and still end up w/ my foot in it sometimes. at 70 (w/out the assistance of my foot) we see a pretty steady 9.9.

at 72 and my foot in it we've rarely experienced anything worse than 8.8

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