100 size tanks?

[Snoweman]

I am getting this seems like a sensitive subject, but on most old school dive ops in Cozumel you don’t see bigger tanks and they are not planned dives at all. I think I have figured out who needs the bigger tanks. Appreciate the responses, I understand.

Aldora has been diving with 120's for years.

I'm not a new diver, but I am a vacation diver - 20 dives a year, tops. Even if I dove more, I don't think I would get more than 50 minutes out of an 80 cf tank on the first dive in Coz.

 

[JFS]

In Cozumel unless the OP has their own tanks, you will be getting a aluminum 100. Only a few shops have their own steel 100. The aluminum 100 will make you more buoyant as it goes below 1000 psi. I always pack extra lead to give at 1000 psi. The steel tanks you will use less lead for sure ,6-8 lbs on average here.

 

[macado]

This primary issue here is that AL80s that the "norm" for 95% of Caribbean dive operators including those in Cozumel. Some of us simply like more gas. I would argue most experienced divers can make an AL80 last a long time but there are factors here. Depth, multi-level, comfort level, current, workload. SAC rate is only one variable.

If the operator only offers AL80s I'll make it work and I'll have a good dive but some of us prefer operators who offer larger capacity steel tanks.

Not counting AL100s (which actually need to be filled to 3300psi and have sub optimal buoyancy characteristics) there are only 3-4 operators in Cozumel that offer higher capacity steel tanks. I'm not going to cheerlead for my favorite operator but it's easy to see who offers larger tanks.

The reality is that steel tanks are expensive and are simply harder to import. It cost the dive operator a lot of money. There is a reason most dive shops use AL80s; they are cheap and ubiquitous. Most divers are perfectly happy with them.

This statement might upset some people but a lot of dive operators who only offer AL80s like to spread the misconception that bigger tanks are only for "gas hogs" or "newer divers." In some cases they are right. Newer divers do go through gas quicker and as a result usually want bigger tanks however there are a lot of experienced divers with good SAC rates that simply prefer larger tanks. We like longer dives and we also like having extra gas.

Sure. Depending on the dive profile I can make an AL80 last 60-75+ minutes. At a place like Colombia Shallows I can easily do a 2 hour dive on an AL80 however my Cozumel dives with larger steel tanks average 75-95+ minutes. Some of these are shorter because I am deeper or hunting lionfish but I've got plenty of 2+ hour dives on a single tank in Cozumel.

Most divers do devils throat and others with 80. The locals do some incredible dives on 80.

This is a poor statement unfortunately. Some locals also do some incredibly stupid dives on an AL80, get bent or kill themselves. There was a very high profile death of a dive operator who liked to bounce dive on AL80s to beat their own personal depth record. That person is no longer alive today.

Devil's Throat / Punta Sur dives tend to be very short bounce dives for a lot of dive operators because of people hitting their NDLs quickly or running low on gas. Just because these dives are done 100 times a day does not make them safe. I'm not saying they are inherently unsafe but nobody can argue that doing these dives with a larger gas reserve is much safer.

TL;DR - Some divers like larger tanks. Some like smaller tanks. Some people are also perfectly fine with a 60 minute dive. I'm not one of them.

 

[brsnow]

This primary issue here is that AL80s that the "norm" for 95% of Caribbean dive operators including those in Cozumel. Some of us simply like more gas. I would argue most experienced divers can make an AL80 last a long time but there are factors here. Depth, multi-level, comfort level, current, workload. SAC rate is only one variable.

If the operator only offers AL80s I'll make it work and I'll have a good dive but some of us prefer operators who offer larger capacity steel tanks.

Not counting AL100s (which actually need to be filled to 3300psi and have sub optimal buoyancy characteristics) there are only 3-4 operators in Cozumel that offer higher capacity steel tanks. I'm not going to cheerlead for my favorite operator but it's easy to see who offers larger tanks.

The reality is that steel tanks are expensive and are simply harder to import. It cost the dive operator a lot of money. There is a reason most dive shops use AL80s; they are cheap and ubiquitous. Most divers are perfectly happy with them.

This statement might upset some people but a lot of dive operators who only offer AL80s like to spread the misconception that bigger tanks are only for "gas hogs" or "newer divers." In some cases they are right. Newer divers do go through gas quicker and as a result usually want bigger tanks however there are a lot of experienced divers with good SAC rates that simply prefer larger tanks. We like longer dives and we also like having extra gas.

Sure. Depending on the dive profile I can make an AL80 last 60-75+ minutes. At a place like Colombia Shallows I can easily do a 2 hour dive on an AL80 however my Cozumel dives with larger steel tanks average 75-95+ minutes. Some of these are shorter because I am deeper or hunting lionfish but I've got plenty of 2_ hour dives on a single tank in Cozumel.



This is a poor statement unfortunately. Some locals also do some incredibly stupid dives on an AL80, get bent or kill themselves. There was a very high profile death of a dive operator who liked to bounce dive on AL80s to beat their own personal depth record. That person is no longer alive today.

Devil's Throat / Punta Sur dives tend to be very short bounce dives for a lot of dive operators because of people hitting their NDLs quickly or running low on gas. Just because these dives are done 100 times a day does not make them safe. I'm not saying they are inherently unsafe but nobody can argue that doing these dives with a larger gas reserve is much safer.

TL;DR - Some divers like larger tanks. Some like smaller tanks. Some people are also perfectly fine with a 60 minute dive. I'm not one of them.

I should have said natives, not locals. I would never do it, seems crazy, but I wonder if those diving there from a young age daily if their boundaries are different.

 

[broncobowsher]

If you are a dive resort, and the staff has to move 100 tanks a day, AL80 for the win. The resort diver who has not been in the water in 4 years and has to carry the rental gear down to the water, AL80 is easier to carry and less likely to get complaints about the tank too heavy to carry. Somewhat poor maintenance, wet fills, aluminum for the win. Buying a new set of tanks in bulk, aluminum is less expensive. Add in most* people can't get into too much trouble on just an 80 if they are paying any attention to there air usage. The AL80 is just perfect for the typical resort use.

Steel is heavier out of the water, but generally more manageable in the water. The 100 just has a lot of the correct characteristics. Once you get past just being able to dive and actually dial in your diving, they work really good. A little extra air in the same size package, nothing wrong there.

 

[macado]

I'm not sure what you mean by "native vs. local" so maybe I'm being obtuse. I don't have a drop of Mayan blood in my body and I can regularly outlast some natives on gas consumption. I'm not anything special. There are a lot of people like that. I know a some local gringos/gringas that live on the island who simply don't breath.

Some natives also do some incredibly stupid dives. The behavior is unfortunately not limited to tourists or local expats. A lot of native fishermen sometimes get themselves badly bent or killed in an effort to feed/support their families.

 

[brsnow]

I'm not sure what you mean by "native vs. local" so maybe I'm being obtuse. I don't have a drop of Mayan blood in my body and I can regularly outlast some natives on gas consumption. I'm not anything special. There are a lot of people like that. I know a some local gringos/gringas that live on the island who simply don't breath.

Some natives also do some incredibly stupid dives. The behavior is unfortunately not limited to tourists or local expats. A lot of native fishermen sometimes get themselves badly bent or killed in an effort to feed/support their families.

I believe the person you referenced who passed away moved to Cozumel, I was referring to those that worked as lobster catchers back in the day and founded the dive industry there and are numerous generations of the family on the boat.

 

[BRT]

In Cozumel unless the OP has their own tanks, you will be getting a aluminum 100. Only a few shops have their own steel 100. The aluminum 100 will make you more buoyant as it goes below 1000 psi. I always pack extra lead to give at 1000 psi. The steel tanks you will use less lead for sure ,6-8 lbs on average here.

And the al100's have about 92 cf at the 3000 # fill pressure you will get.

 

[Tracy]

If you are a dive resort, and the staff has to move 100 tanks a day, AL80 for the win. The resort diver who has not been in the water in 4 years and has to carry the rental gear down to the water, AL80 is easier to carry and less likely to get complaints about the tank too heavy to carry. Somewhat poor maintenance, wet fills, aluminum for the win. Buying a new set of tanks in bulk, aluminum is less expensive. Add in most* people can't get into too much trouble on just an 80 if they are paying any attention to there air usage. The AL80 is just perfect for the typical resort use.

Steel is heavier out of the water, but generally more manageable in the water. The 100 just has a lot of the correct characteristics. Once you get past just being able to dive and actually dial in your diving, they work really good. A little extra air in the same size package, nothing wrong there.

I'm not sure where you get your information, but steel tanks are lighter than aluminum.
An LP80 weighs about the same as an AL80
A HP80 weighs a lot less than an AL80
Same for 100s, an AL100 weighs as much as a LP104.
An hp100 is way lighter than either.
Aluminum tanks win in price, that is about it. They are as heavy or heavier on land and much lighter in the water.

 

[ggunn]

I believe the person you referenced who passed away moved to Cozumel...

Is there some reason why we are not mentioning her name: Opal? I knew her briefly; she was for a time a DM/instructor at Blue Angel.