I'll be cruising with them and they may sit full, then near-empty, for
periods of time. Anyone have suggestions, favorites, warnings, etc.
Thanks,
Brad Snow
s/v Aldonza

Depends on what you mean by periods of time but then, you should have
learned that in your scuba level 1 training.

Valid hydrostatic (5 years)
Annual valid visual inspection
air breathed shouldn't taste funny

After this, you must rather insure on the way the compressors where
you fill are well maintained by the station's operator and that he
doesn't fill the bottle with CO, nor oil, nor humidity. Insure the
intake is far from any exhaust source ant that filters (oil and water)
on the compressor are regularly purged and changed. Eg: don't fill 'em
up in cheap holes on the beach. Refill in a responsible and
sanctionned (PADI-NAUI-ACUC-or other diving Intl regulation
organisation) filling station. Your lungs are at stake here. In the
unlikely case of damage from one of a sanctionned outlet, you'll be
covered by their insurance program at least, which might not be the
case for a native running a compressor in hut on a beach in the
Caribeans. Ask for their licence and ask to see the compressor and the
location of the intake.

If at rest for long, I prefer to keep some pressure in the tank to
keep any humidity out of it than having no pressure whatsoever.
Fatigue from the various filling and emptying is what weakens
eventually the tank rather than when sitting unused at whatever
pressure. But you may want to keep them protected from the sun and
temperature variations in the boat though, especially when full. You
will also want them out the way and held tight in place. Tanks and
lead belts swinging in a cockpit can really ruin a gelcoat! That's why
I stopped diving from my own boat!!! ;-)

Jean Dufour
Former PADI Divemaster

padeen wrote:

I'll be cruising with them and they may sit full, then near-empty, for
periods of time. Anyone have suggestions, favorites, warnings, etc.
Thanks,
Brad Snow
s/v Aldonza

All good advice, Jean; thanks. But my main consern is about which kind
(material) of tank would suit.


"Jean Dufour" wrote in message
...
Depends on what you mean by periods of time but then, you should have
learned that in your scuba level 1 training.

Valid hydrostatic (5 years)
Annual valid visual inspection
air breathed shouldn't taste funny

After this, you must rather insure on the way the compressors where
you fill are well maintained by the station's operator and that he
doesn't fill the bottle with CO, nor oil, nor humidity. Insure the
intake is far from any exhaust source ant that filters (oil and water)
on the compressor are regularly purged and changed. Eg: don't fill 'em
up in cheap holes on the beach. Refill in a responsible and
sanctionned (PADI-NAUI-ACUC-or other diving Intl regulation
organisation) filling station. Your lungs are at stake here. In the
unlikely case of damage from one of a sanctionned outlet, you'll be
covered by their insurance program at least, which might not be the
case for a native running a compressor in hut on a beach in the
Caribeans. Ask for their licence and ask to see the compressor and the
location of the intake.

If at rest for long, I prefer to keep some pressure in the tank to
keep any humidity out of it than having no pressure whatsoever.
Fatigue from the various filling and emptying is what weakens
eventually the tank rather than when sitting unused at whatever
pressure. But you may want to keep them protected from the sun and
temperature variations in the boat though, especially when full. You
will also want them out the way and held tight in place. Tanks and
lead belts swinging in a cockpit can really ruin a gelcoat! That's why
I stopped diving from my own boat!!! ;-)

Jean Dufour
Former PADI Divemaster

padeen wrote:

I'll be cruising with them and they may sit full, then near-empty, for
periods of time. Anyone have suggestions, favorites, warnings, etc.
Thanks,
Brad Snow
s/v Aldonza

are you cruising internationally??? Go Aluminium...It is very
difficult to get a 3500 fill in the bahamas. They are cheaper and
forgiving.

Are you really good on air consumption and have access to 3500 fills and
they are stored in an area that may get damp but does not stay wet?
Get a 120 steel high pressure (Same diameter as an 80- Alum but a bit
taller) This is my tank of choice for cruising... I do 2 long dives
back to back on this tank... saves storage because I only need one. I
do use these in the islands but I usually only get a 2900 PSI fill
there. I only do short cruises (10 days max... pesky job thing..) so I
take 2 of these, do 2 days (4 dives) of diving, fill them and then do 2
shorter days of diving. BTW.... the new ones come in 3490 version and
have YOKES.... No need to convert to DIN anymore (although all my regs
are DIN...historical thing)

Low pressure steel? Not a terrible choice for long range but they are
HEAVIER by far for the same amount of air.

EIther way... NEVER let any tank, especially steel sit 100% empty.

ALSO... INVEST IN AN EQUALIZER.....This is a simple device with two
yokes and a hose in the middle and a bleeder on one end. (THIS IS NOT
TWO FIRST STAGES....THEY WILL NOT WORK) This is used when you have a
full tank but your buddy only has 500 LBs.... Hook the tanks together
and EQUALIZE them to 2000 so you can both dive. For cruisers, this is
a great tool to get an extra dive. I use mine all the time.





padeen wrote:

All good advice, Jean; thanks. But my main consern is about which kind
(material) of tank would suit.


"Jean Dufour" wrote in message
...

Depends on what you mean by periods of time but then, you should have
learned that in your scuba level 1 training.

Valid hydrostatic (5 years)
Annual valid visual inspection
air breathed shouldn't taste funny

After this, you must rather insure on the way the compressors where
you fill are well maintained by the station's operator and that he
doesn't fill the bottle with CO, nor oil, nor humidity. Insure the
intake is far from any exhaust source ant that filters (oil and water)
on the compressor are regularly purged and changed. Eg: don't fill 'em
up in cheap holes on the beach. Refill in a responsible and
sanctionned (PADI-NAUI-ACUC-or other diving Intl regulation
organisation) filling station. Your lungs are at stake here. In the
unlikely case of damage from one of a sanctionned outlet, you'll be
covered by their insurance program at least, which might not be the
case for a native running a compressor in hut on a beach in the
Caribeans. Ask for their licence and ask to see the compressor and the
location of the intake.

If at rest for long, I prefer to keep some pressure in the tank to
keep any humidity out of it than having no pressure whatsoever.
Fatigue from the various filling and emptying is what weakens
eventually the tank rather than when sitting unused at whatever
pressure. But you may want to keep them protected from the sun and
temperature variations in the boat though, especially when full. You
will also want them out the way and held tight in place. Tanks and
lead belts swinging in a cockpit can really ruin a gelcoat! That's why
I stopped diving from my own boat!!! ;-)

Jean Dufour
Former PADI Divemaster

padeen wrote:

I'll be cruising with them and they may sit full, then near-empty, for
periods of time. Anyone have suggestions, favorites, warnings, etc.
Thanks,
Brad Snow
s/v Aldonza

Thanks Ed. And the equalizer sounds invaluable.