cruising with full water tanks?

[Terry Forshier]

I am getting ready to sail off for a few days cruising in the Keys and a lot of it will be motoring in pretty shallow water. Since i stay at marinas about half the time and only anchor and shower out ocassionally I am wondering why I always top off the water tanks and carry the #640 of water everywhere I go.  (8.4 # per gallon x 77 gallons)It seems I would get better speed/mileage and sit higher if I just took on about 1/4 of the water. Is there a reason to keep the tanks filled or just a hang over from when I used to anchor out and skimp on water and battery? 

[Stu Jackson]

Hi, Terry, nice to have that cruising background with full water tanks.  We do a bit of cruising, too, and purchased one of those Scanvik water saver wands that fits into the galley faucet spigot.  It sure would work for being out on the hook, but I keep it in the drawer when we're close to easy water sources.  That said, one of our Fleet 1 members, a perennial racer and winner here, has nothing but water vapor in his tanks!  We recently cruised in together and he noted his brand new water pump seemed to on the fritz and was running in an odd manner.  He took off his starboard tank inspection plate and found literally nothing!  He'd put a few gallons in to please his wife, but I guess she washed her hands once too often.

As far as I know, other than making sure your water pump isn't on and trying to burn itself out, there is no reason to not run with empty tanks.

[David Sanner]

You might try only using one tank.  This way the water is fresher
and with frequent marina stops it doesn't sound like you'll run out.

I keep my aft tank dry and use the starboard tank to keep
the weight low and out of the ends.

This can also help with the port list if you have any.

[Jon Schneider]

Terry, I think our cruising habits and water needs are similar to yours.  After installing a below-deck autopilot last year, I still haven't gotten around to replacing the aft tank, which I rarely used anyway.  I will re-install it just for the sake of completeness, but I won't fill it up.  I keep my starboard tank full (perhaps if I prepped for a race, I'd be tempted to empty it if I remembered) to help with C34 port list (and, of course, to be able to wash my hands).  I actually hate the aft tank, since when it's half full, its lateral position wreaks havoc on your balance by swishing from side to side as the boat heels.  I have even contemplated getting a new, slightly smaller tank (say 35 gals) and building a new platform for it that would run fore to aft on the starboard side, thus completely solving the port list.  As far as cruising comfort goes, I don't think you'll have a problem.  It would be better if you had tank monitor, though.

[Steve Sayian]

The MK II's have their tanks forward under the Vee berth (25 Gals (a C-30 tank)) and 40 gals aft under the aft end of the cockpit (unted athwartships). Neither tank is baffled and as the water in the aft tank is used, it makes a hell of a banging sound when at anchor/mooring (which is why we sleep in the vee berth).
We typically use the aft tank and keep the forward tank as full as possible to keep the weight in the bow for better performance with the standard 135% genny.

[Ron Hill]

Terry : I assume that you have a MK1 ?  As Jon mentioned you might consider just keeping the starboard tank full as it keeps the boat in trim. 
If you have never been to the Keys, they used to have a water restriction that you could fill your water tanks, but could NOT wash off your boat with fresh marina water(water is imported from Miami in a pipe line down Rt 1)!!  For that reason I'd fill all tanks and at least be able to take a bucket full of fresh water from you own faucet to slosh down the deck/anchor well - if needed!! 
I don't think that those few extra pounds of water will increase the hulls wetted surface that much that (when cruising) will "slow" you down that much.  A thought