One fresh water tank, or two?

[BdoubleU]

So my girlfriend and I have decided that we want to install about 100 gallons of fresh water underneath our skoolie. I've been thinking it might be advantageous to go with (2) 50 gallon tanks instead of one large tank. One tank would be primary and the other one would only be used for extended off-grid stays. My thinking is that for 2-3 night stays the 50 gallon tank should be plenty and a smaller tank may help to eliminate some of the sloshing forces while driving. Does this sound like a reasonable idea or just unnecessary?

If I did go with two tanks is there any special plumbing considerations I should be aware of?

Would this thinking make sense for the grey water tank as well?

Thanks,
Brandon

[rffffffff]

I’m no expert in this but it seems like a good idea to me. A single 100 gallon tank is 800 lbs so 50s are way more manageable. Sloshing forces are real. Let’s just say a guy I know might’ve dropped a tank when the straps failed. Whoops!

[o1marc]

I have a 35 gallon tank under the sink cabinet, a second 40 gallon tank in the storage bin below the cabinet. I fill the upper tank that gravity feeds the lower tank. Pump draws from the lower tank. So It's easy to tell when water is needed by looking under the sink at the top tank, when it's empty, you're still more than half.

[Rucker]

The primary benefit of two tanks (either fresh or graywater) is it gives you greater flexibility in placement.

[LargeMargeInBaja]

We use more than two fresh-water tanks!
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I worked burger joints in the 1960s, so I wondered if I could use retired five-gallon stainless-steel Pepsi kegs...
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I discovered these are popular with home-brewers of beer and kombucha.
I fabricated a rack for seven inside the rig, plus we can carry couple-three dozen in the toy-hauler.
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Advantages:
* modular -- we can camp with a few, or take our entire inventory
* isolate contamination -- we can use the others if one gets stanky
* we can take some to re-fill in town while using the camp-stayers
* portable -- we can move one to a picnic-table or camp-fire
* separable -- we can loan one to a caravan chum.
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With a quick puff from a 12vdc bicycle-tire pump to slightly pressurize a keg, water flows from a kitchen-sink sprayer designed for a stand-still house.
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For showers, we use a dedicated three-gallon 'Torpedo' keg.
We heat that water using 'sous vide' circulation heaters designed for gourmet cooking.
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*****
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If you decide on big fixed tanks, please consider filtering all water going in.
One of my hobbies is walking wrecking-yards.
Factory RecreationVehicles in the dismantling process with exposed innerds show the results of putting unfiltered water into a tank -- layers of sludge often inches deep.
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I would be uncomfortable with that.

[Iceni John]

I have two 110-gallon fresh water tanks in my bus, either side of the fuel tank and just behind the front axle. Each tank hangs by ten 1/2"-threaded hangers, and is sheathed on all four sides and bottom with 1/2" plywood. They each have a 3/4" ball valve at their outlets, and they are inter-connected with a length of 3/4" galvanized pipe that has a drain valve at one end. This means that I can completely drain either tank if needed, or shut off one of the tanks if needed. Each tank has its own gravity-feed inlet that's a stainless-steel marine deck fill, much nicer than the usual plastic RV crap. Either or both tanks can also be filled from the shore water connections by simply opening one valve next to my pumps. The tanks were roto-molded by Ronco Plastics in Tustin CA from 3/8" polyethylene, with spin-welded fittings for their inlets, outlets and vents. In addition, the left tank has a pair of 1/4" fittings for a sight glass to see its water level; it also has a 1/2" fitting in the top for a return line from the bathroom sink's faucet so I'll be able to run the not-yet-hot water back into the tank instead of wasting it while waiting for it to get hot. So far, so good.

John