All About Tanks.... Size, Make, Contents, Ops, Etc.

[John Trecker]

Planning 8 days of diving in Cozumel and trying to work out the situation with tanks and impact on ops selection, dive time, price, etc. I have searched to see if there was a consolidated thread, but could not ID one (especially not recent). And there seems to be general consensus that this could have a big impact on experience. On top of this, when I have reached out to dive operations to understand options, I seem to be getting a lot of... 'all the same makes no difference'.
Hoping to maybe get here some consolidated input / advice especially as may affect air vs nitrox.
PS: And remember that old saying... its not the size of the tank, but the motion of the ocean and the length of the trip....

 

[rick00001967]

i am not even sure what you are asking.

are you looking for shops with larger tanks and longer dive times ?

 

[ggunn]

Planning 8 days of diving in Cozumel and trying to work out the situation with tanks and impact on ops selection, dive time, price, etc. I have searched to see if there was a consolidated thread, but could not ID one (especially not recent). And there seems to be general consensus that this could have a big impact on experience. On top of this, when I have reached out to dive operations to understand options, I seem to be getting a lot of... 'all the same makes no difference'.
Hoping to maybe get here some consolidated input / advice especially as may affect air vs nitrox.
PS: And remember that old saying... its not the size of the tank, but the motion of the ocean and the length of the trip....

Aldora and Living Underwater use 120ft^3 steel tanks while 80ft^3 aluminum tanks are the standard everywhere else, although 100ft^3 aluminum tanks are available at many/most/all ops that use aluminum. Nitrox may or may not be an upcharge.

 

[gopbroek]

Recently @jonhall put together a very nice sheet that answers a lot of your questions

Finding a (Best) Dive Op in Cozumel

As for tank size, the standard tank used in Cozumel is the ubiquitous AL80 but most operators will also have AL100's that they either own or can rent (if they are using Maridiano as a filler, they may get short fills @ 3000PSI or less). Three (late edit, Two) operators, that I am aware of, use steel 120's. To the best of my knowledge there are not any rentals or 'loaner' 120's available.

All are available in either air or Nitrox (32 or 36). When everything is working right Cozumel is about long drift dives, often at depth, with the current and minimal energy expended on swimming. This often leads to NDL limitations as opposed to gas limitations on dive times which is why nitrox is very popular on the island.

Different shops have different dive styles, ask. Many are tight group dives with everyone in and out at the same time, this may lead to a short dive if one or several divers have high air consumption, regardless of the size of the tank. Others will feed higher air consumption divers to the surface with the DM below running a buoy and allow the other divers to finish their tanks (my LDS does this and I typically get 70+ minutes on a AL80 tank, including going over the wall looking for Pez Leon). Others I have heard are on a strict 45 or 60 minute dive plan due to boat utilization scheduling (I have heard this about some inhouse / cruise ship contract shops but I have not experienced it).

Some dive operations handle and clean all your gear, some don't. Some provide transportation, some don't. The main thing is to communicate with your prospective dive shop and do not be bashful about asking questions. Not everyone dives the same way or has the same expectations but the key is to find the operator that fits you.

 

[horn34]

Aldora and Living Underwater use 120ft^3 steel tanks while 80ft^3 aluminum tanks are the standard everywhere else, although 100ft^3 aluminum tanks are available at many/most/all ops that use aluminum. Nitrox may or may not be an upcharge.

Jeremy switched to LP95's

 

[rick00001967]

i hope people also take the weight of these larger tanks into account when they decide to use them. i know divers that wear 3mm full suits (although their old suit is probably more like a 1mm now haha) when diving salt water with an allum 80 and do not need any extra lead.

i am not one of those divers.

i have never had a need for a larger capacity tank. as stated in the post above, my NDL has almost always been the limiting factor.not gas supply.

 

[ggunn]

Jeremy switched to LP95's

Which others besides Aldora use 120ft^3 steel?

 

[horn34]

Which others besides Aldora use 120ft^3 steel?

Liquid Blue, not sure who else

 

[rick00001967]

aldora and liquid blue, according to that pdf with all the shop info are the only ones listed as having 120's. unless i missed one.

 

[gopbroek]

Jeremy switched to LP95's

Thank you, I thought Jeremy was running 120's