Tank Sizes - Too small?

I am not totally clear on how many gallons capacity each tank is, but approximately, I have a freshwater tank  ~50 gallons, a blackwater tank ~38 gallons and a greywater tank ~20-some.

When we four camped after Friday evening thru Sunday morning, we had maxed out the greywater tank into the shower (which was clean, blue backup water, no problem, whew-lucky), had several inches remaining in the freshwater tank and almost nothing in the blackwater tank.

I have several inches of room above my greywater tank, airspace between the floor above it and top of the tank which means I may be able to install a larger greywater tank.

When I drained the tanks, I had ~30 seconds at most draintime of the black tank and then the grey tank seemed to drain for at least 2.5 minutes. I realize the line size is smaller on the grey tank and will flow slower but clearly there was a huge difference.

So...it seems kind of backwards to me. I am trying to gear up for dry camping. It seems that a shower and a galley sink drain quite a bit more water than a head & would need more capacity not less. What is normal for grey/black/fresh?



Options may include:
A) An overflow line & check valve from greywater to blackwater tanks. ($)
B) A new larger greywater tank ($$)
C) Capturing sink water in a tub, carrying it to the head > blacktank (free)
D) Both  ($$$)
E) Other solution that I have not thought of yet

Sidebar: Gages
The dang tank level gages refuse to be unclogged so far. I can't bring myself to fill up that much water just to do a full rinse. I bought the gage rinsing juice and applied it this weekend, but it did not so far succeed. Having working gages would be nice. They indicate full for the grey & black tanks. I would have thought the cleaner juice on the full grey tank would be successful but it was not. That junk was $15. Does it ever work? Should I do it again & sacrifice the 50 gallons of water to do so?

anemic said:

Sidebar: Gages
The dang tank level gages refuse to be unclogged so far. I can't bring myself to fill up that much water just to do a full rinse. I bought the gage rinsing juice and applied it this weekend, but it did not so far succeed. Having working gages would be nice. They indicate full for the grey & black tanks. I would have thought the cleaner juice on the full grey tank would be successful but it was not. That junk was $15. Does it ever work? Should I do it again & sacrifice the 50 gallons of water to do so?

Click to expand...

I would fill up the gray and black water tanks about 3/4+ with water, add some Ridex, dry around a little to shake things up, then let sit for a day or two, then dump.

In normal use you should be using quite a bit of water with your solid waste and not dumping your black tank until it is somewhere around 2/3 full. The more water in the black tank, the cleaner it will stay.

Conservation is the key to boondocking.  G.I showers are almost mandatory.  Some use baby wipes for daily cleaning and shower infrequently.  A solar shower can be a good alternative too.

Another trick is to do dishes in a dishpan and dispose of it in either the black water tank or outdoors. 

The problem is not the size of the tanks, it is the length of a shower. An Rv shower should take no longer than one minute and use no more than one gallon of water. Anything more than that and you are wasting water. Four people in one RV will max out a tank in a big hurry otherwise.

We've run into similar problems and choose to go the path of a porta tote and store it on a hitch hauler.  The hitch hauler lets us carry the little extras that just don't quiet fit right in the basement like firewood, portable gas can for generator and such.  There's down sides though especially winter camping when it freezes the tank, that was a fun experience...  otherwise it's been a great device for extra capacity.

If i had the knowledge I would look at increasing the tank sizes, especially since we noticed all the extra space where the fresh water tank is!!!  Let me know if you go the route of replacing the tanks I'd enjoy following that project.

Dave

I'll show my long haired 12 y/o daughter a picture of Sinead O'Connor and discuss water usage.

The 12 year old definitely needs to be reeducated. As far as the tank gauges go, they rarely work in RVs. In fact they have never worked in any RV I have ever owned. I would not trust them if they did. I can see the level in my fresh water tank by opening a basement door and I can see the level of my black water tank if I look down the toilet with the valve open. So I am never guessing.

There are alternatives. You can stay at places that have public showers. You can stay at places near lakes, streams or oceans. You can stay near a motel and sneak into the pool. Or you can invest $10 in a pair of hair clippers.

she does pretty well on the boat with a bucket of Lake Michigan. 

I am planning to be off the grid in the winter skiing for the most part so the solution is education & small mods.

Grey to Black Overflow Bypass is an innovation of mine? Really? Patent pending! Dibs!

Another thing I might do is put a 1/4" or 3/8" line, or choke point in the shower line. Like a water saver faucet.

Hey I'll do that in all the sink faucets too. I did them at home. Why not the rig. Of course!

There are other products that couple the gray and black tanks, though they usually come as part of a macerator pump set-up.. Heck, you can usually do it just be keeping both valves open, letting the level in the two tanks equalize (cap must be on the outlet!). Gets really yucky if that backs up into the shower, though!

Normally the gray tank is larger than the black, so I am doubtful of your capacity numbers. If you have a trailer with a rear kitchen or bath, you may have two gray tanks, though, and one of them can be small.  And the gray tank takes much linger to drain than the black - the black waste gate is about 4x the size of the gray.

You can get water saver washers to insert in a shower fixture - basically just a washer with a small hole in it. It will make your daughter very unhappy and she will stay in the shower even longer.

You can clean the gauge sensors by filling the tank and adding a septic tank enzyme like Rid-Ex or Roebic 57. It will have to sit 3-4 days, though. A more permanent fix is to add See-level gauges, which are external to the tank.  I've also seen some positive reports on the Horst tank sensors, which is an improved model of in-tank sensor.

Horst probes it is! Thank you. What a neat solution!

Also: water savers all around. and the dishpan bucket > head trick.

I am hesitant to do the over flow line because then I might have to add more pipe heaters. Or perhaps I have do some clever valve...like the grey dump valve. hm.

I may have the tank capacities swapped. will double chk w/Tiffin.

Thanks for the great tip on Horst probes Gary! Will DO!

Edit: right. just open the valves to parallel the tanks...clever. There will be a small quantity of grey-black spillage at dump time as a result. Whatever is the capacity of Y valve connection. Rinseable & tolerable. Thats what my disposable gloves are for. And that nearby hose of non-potable water. No added expense, projects or heat tracing. Yes, nice.

Hello anemic.

My trailer has a 55 gallon freshwater tanks and 40 gallons each for greywater and black.

In general, black tanks are sized large enough to allow for the common situation where there is a water supply and a means of disposing of greywater but no practical means of disposing of sewage.  People use the blue totes for greywater, for example, but they aren't really suited to handling sewage (though it can be done).  There are also a few jurisdictions where it is acceptable to dump greywater on the ground or in a hole or simple trench.

I have a family of 5 and find that in practice we can't go more than one night self contained unless I act as the water police which is not the kind of interaction I want to have with my kids while we're on vacation.  So either we stay at places with hookups or figure out a way to dump the tanks every night.

Jammer I know how you feel about how we balance our approach w/the kids, fun versus utility.

Update on tank capacities:

gas 60g
freshwater 45g
grey & black are both 32g, same size

I have been dry camping off and on for the past couple of months with the trailer in one spot. With no practical means of emptying either black or grey tanks, we were a) very judicious with our use of water, and used the outhouse in the campground more often than the toilet in the trailer, and b) I stuck a small bin in the kitchen sink to capture our tap water and to do dishes. The campground owner suggested I just dump the bin in the bushes and it would be fine, as long as it was just grey water. I've been unable to source one of those portable tanks locally so far, and even if I could, it's unlikely I would be able to lift it when it was full anyway.

The upshot is that in 14 days I still had next to nothing in the grey water tank.

Oh, we rarely shower in the trailer. It's simply water that I don't want to part with, and refilling the tank with water jugs is no fun task in the rain. So we just use the campground shower. Easier, we can take longer showers, and I save my water

I have a third twist-on waste valve that I keep closed when I want to open the black and grey tanks to equalize them.

Valterra-T58-Twist-On-Waste-Valve

Gary RV Roamer,

I wanted to give you an update on the Horst Probes. Thanks again for the tip. They work just great. It inspires peace of mind actually having the monitor display accurate tank levels.

I still think it would be great to have a composting head and convert the black tank to grey water use. But that is a ways down the list and composting requires a heat source, which becomes tricky for winter use.

Thanks for the report - feedback like that helps us to help others in the future.