Hi,

I've always seen plastic watertanks, but the boat I'm buying has an old
aluminum one (I think it's alum: it's metal, and not SS). Is there any
advantage to alum over plastic or vice-versa? I'm planning on replacing it
with a bigger one, and first I thought plastic, but should I consider
aluminum instead? I've always disliked the "plastic" taste in the water
from a plastic tank.

druid
http://www.bcboatnet.org

On Tue, 02 Oct 2007 12:40:40 -0700, druid wrote:

I've always seen plastic watertanks, but the boat I'm buying has an old
aluminum one (I think it's alum: it's metal, and not SS). Is there any
advantage to alum over plastic or vice-versa? I'm planning on replacing it
with a bigger one, and first I thought plastic, but should I consider
aluminum instead? I've always disliked the "plastic" taste in the water
from a plastic tank.

My old boat had an aluminum water tank and it was fine. The one
before that was stainless steel. My present boat has black iron
(steel) tanks. No problems with any of them. On the other hand if
the plastic tank is properly designed and mounted, and sheilded from
UV damage, it should last a long time.

On Tue, 02 Oct 2007 12:40:40 -0700, druid wrote:

Hi,

I've always seen plastic watertanks, but the boat I'm buying has an old
aluminum one (I think it's alum: it's metal, and not SS). Is there any
advantage to alum over plastic or vice-versa? I'm planning on replacing it
with a bigger one, and first I thought plastic, but should I consider
aluminum instead? I've always disliked the "plastic" taste in the water
from a plastic tank.

A charcoal filter will take out the taste.

Casady

On 2007-10-02 15:40:40 -0400, druid said:

I've always seen plastic watertanks, but the boat I'm buying has an old
aluminum one (I think it's alum: it's metal, and not SS). Is there any
advantage to alum over plastic or vice-versa? I'm planning on
replacing it with a bigger one, and first I thought plastic, but should
I consider aluminum instead? I've always disliked the "plastic" taste
in the water from a plastic tank.

I prefer aluminum over plastic and wouldn't replace a perfectly good
tank with a bigger one, but would add tanks in otherwise unused corners
of the boat.

Our tank is plastic. We have a filter in-line for mostly sediment but
the charcoal element removed the last of the plastic and other
objectionable components (unless I leave the tank full for a Chesapeake
summer week or three, which will overload any filter.)

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's new pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI pages: http://homepage.mac.com/jerelull/BVI/

On Oct 2, 4:41 pm, Jere Lull wrote:
... wouldn't replace a perfectly good
tank with a bigger one, but would add tanks in otherwise unused corners
of the boat. ...

This seems like good advise. I keep hearing horror stories of folks
draining all their drinking water into the bilge when they spring a
pressure water leak. I always turn my pressure water off at the panel
when it isn't in use, but also have two tanks that are isolated so it
takes a greater level of idiocy to dump all the fresh water. I also
like to make my water into a working tank and keep a known good tank
in reserve in case something goes wrong there.

-- Tom.

On Oct 2, 7:41 pm, Jere Lull wrote:
On 2007-10-02 15:40:40 -0400, druid said:

I've always seen plastic watertanks, but the boat I'm buying has an old
aluminum one (I think it's alum: it's metal, and not SS). Is there any
advantage to alum over plastic or vice-versa? I'm planning on
replacing it with a bigger one, and first I thought plastic, but should
I consider aluminum instead? I've always disliked the "plastic" taste
in the water from a plastic tank.

I prefer aluminum over plastic and wouldn't replace a perfectly good
tank with a bigger one, but would add tanks in otherwise unused corners
of the boat.


(Wow - I really started a war on this one - sorry!)

All things being equal, I'd agree: add a tank rather than replace.
However, this is a 28-ft boat and there aren't a lot of options. The
existing tank is cylindrical, with no access port. And it's sitting
under the V-berth, where there's lots of room for more tanks.... if
this was was taken out. So my Plan is to remove the existing tank, put
in a platform where the old tank was, and put in His'n'hers water and
holding tank. I can't do that without removing the existing tank
(which sounds like not a bad idea anyway: better safe than sorry for
an unscrubbable, un-lineable aluminum tank!)

druid
"Coatue" Crown 28

On 2007-10-15 11:41:21 -0400, druid said:

On Oct 2, 7:41 pm, Jere Lull wrote:
On 2007-10-02 15:40:40 -0400, druid said:

I've always seen plastic watertanks, but the boat I'm buying has an old
aluminum one (I think it's alum: it's metal, and not SS). Is there any
advantage to alum over plastic or vice-versa? I'm planning on
replacing it with a bigger one, and first I thought plastic, but should
I consider aluminum instead? I've always disliked the "plastic" taste
in the water from a plastic tank.

I prefer aluminum over plastic and wouldn't replace a perfectly good
tank with a bigger one, but would add tanks in otherwise unused corners
of the boat.


(Wow - I really started a war on this one - sorry!)

Nothing to be sorry about. The thread ceased to be about the subject
very early.

All things being equal, I'd agree: add a tank rather than replace.
However, this is a 28-ft boat and there aren't a lot of options. The
existing tank is cylindrical, with no access port. And it's sitting
under the V-berth, where there's lots of room for more tanks.... if
this was was taken out. So my Plan is to remove the existing tank, put
in a platform where the old tank was, and put in His'n'hers water and
holding tank. I can't do that without removing the existing tank (which
sounds like not a bad idea anyway: better safe than sorry for an
unscrubbable, un-lineable aluminum tank!)

druid
"Coatue" Crown 28

Xan's also a 28, but we have so many unused corners, I forget that not
all boats do. (diagram on Xan's "interior" pages doesn't quite show all
our stowage.)

I'd say get Peggie Hall's book on sanitation, of course, and suggest
that you double the size of the holding tank you envision (ours is 40
gallons and sometimes we have to leave anchorages early). I've come to
agree with Ms. Head Mistress that the holding tank ideally should be in
the bottom of the "V", with two large vents to either side of the hull
for cross-flow.

I like the water tank(s) to be as far away from the ends of the boat as
possible -- while maintaining trim on the boat, so you may have to move
something forward from the transom in the process.

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI trips and tips: http://homepage.mac.com/jerelull/BVI/

"druid" wrote in message
news
Hi,

I've always seen plastic watertanks, but the boat I'm
buying has an old
aluminum one (I think it's alum: it's metal, and not SS).
Is there any
advantage to alum over plastic or vice-versa? I'm planning
on replacing it
with a bigger one, and first I thought plastic, but should
I consider
aluminum instead? I've always disliked the "plastic" taste
in the water
from a plastic tank.


you still have 'plastic' lines, don't you?

Scotty

An aluminum tank will be attacked by any chlorine in the water, plus
you 'really' need to install a magnesium removeable anode.

The chlorine attack will prevent you from chlore shock sanitization
and/or keeping a small concentration of chlorine to keep down the
growth of fungals and bacteria.

The BEST probable solution is to use aluminum (with baffles) and then
put an FDA/NSF approved 'lining epoxy' on the inside to render the tank
safe for chlorination, etc. Such lining epoxied can be applied with a
roller and brush (after sanding, etc. to make the aluminum 'bright').
Youll want: rated for POTABLE water and has the FDA/NSF
'certifications'; if you use 'common' epoxy you will get a high
concentration of 'leachables' in the water. This stuff is pretty
easy to 'roll-on'.
Do websearch for NSP-120 or go to the 'commercial' division of Interlux.
Such tank 'lining' in the marine and transportation industry is quite
common.
The advantage of lining a metal tank is that the tanki can have BAFFLES
which is impossible with a roto-molded 'plastic' tank.

On Oct 8, 11:19 am, Rich Hampel wrote:
An aluminum tank will be attacked by any chlorine in the water, plus
you 'really' need to install a magnesium removeable anode.

The chlorine attack will prevent you from chlore shock sanitization
and/or keeping a small concentration of chlorine to keep down the
growth of fungals and bacteria.

The BEST probable solution is to use aluminum (with baffles) and then
put an FDA/NSF approved 'lining epoxy' on the inside to render the tank
safe for chlorination, etc. Such lining epoxied can be applied with a
roller and brush (after sanding, etc. to make the aluminum 'bright').
Youll want: rated for POTABLE water and has the FDA/NSF
'certifications'; if you use 'common' epoxy you will get a high
concentration of 'leachables' in the water. This stuff is pretty
easy to 'roll-on'.
Do websearch for NSP-120 or go to the 'commercial' division of Interlux.
Such tank 'lining' in the marine and transportation industry is quite
common.
The advantage of lining a metal tank is that the tanki can have BAFFLES
which is impossible with a roto-molded 'plastic' tank.

problem is on a normal baffeled tank of any size (under the size a man
can crawl thru the baffles) is painting it with a brush or roller is
next to impossiable, unless the tank has an inspection/work port in
every space between baffles. It's a great way to go if your building
tanks but expensive to do right. And roto mold tanks can and do have
baffles. They are made by molding deep V's into the sides of the
tanks.

Joe