Al100 Vs. Al80

[RonFrank]

Hi everybody, I am new to diving and am looking into buying a tank or two. My question is, how much more time underwater would the average diver have while using an AL100 vs. and AL80 at the same depth? Thanks

Most divers I know get NO more time UW when using an AL80 vs. an AL 100. This is based on the fact that if one is not an air hog, the average diver will reach their NDL before they run out of air in an AL80.There are exceptions one being when diving Nitrox 36 for example doing a flat profile at 80 feet.

The second limiting factor for BT is generally the Dive Op. IOW's most dive ops are NOT gong to allow one to do a 2 hour dive on a 30~40 reef even if one has enough air, and NDL.

AL80's are popular because most divers can hit their NDL without running out of air. IMO having a couple AL80's is not a bad thing, and if I lived where I could haul my tanks to say Jupiter, FL, I'd also be looking at getting STEEL 100's for those flat profile Nitrox dives that are so fun to do in that area.

The original question is good, but the fact that you asked leads me to believe that you need to do a bit more diving to determine what YOU need. Some divers use AL100's for EVERYTHING. My buddy is a big guy, with big lungs, and uses AL100's because his SAC rate is not going to ever get close to that of a typical average size diver, or at least after around 100 dives it has not.

 

[SHRIKE]

I was mainly looking for something that would let me enjoy more time on shallow dives and be at least as good as an AL80 on deep dives. I figured that I would get more time underwater with the AL100 when shorediving in places like Maui. I could spend more than 2 hours in 40 ft. of water right off the beach if I had enough air.

 

[LobstaMan]

IMHO...spend the money on a matched pair of steel 100s or 95s and you'll be much happier in the long run. My brother has a couple of AL100s and has used them in the past, but doesn't like them that much, so he doesn't use them anymore. I can't remember his specific complaints, but I do think he said that they are too heavy out of the water, too tall/long and when close to empty are a bit bouyant. He usually uses steel 72s or AL80s now, although I'm trying to get him to go steel HP100 like me. He's a member of the SB(scubastew), so maybe he'll read this thread and chime in.

LobstaMan

 

[ClayJar]

If you're shallow enough not to hit NDLs, you can get in longer dives on an AL100 (my longest was 2:47 on one AL100 at a 17-foot average depth). If you hit your NDLs, well, you'll just have more reserve gas, which is hardly a bad thing.

I find no significant difference in diving my AL100s as opposed to my AL80s. Other than the initial price and the 10 added pounds, there's no reason you can't do everything on a AL100 you could do on an AL80.

(I also dive nitrox on my AL100s. It lets me make better use of the added capacity, as I can stay on the bottom longer. If I'm diving 36% around 80 feet, the extended NDLs are really nice.)

 

[paulwlee]

I figured that I would get more time underwater with the AL100 when shorediving in places like Maui.

I see you are in Louisiana. If you were thinking about taking your tanks for vacation, that's not a good idea. Everybody rents tanks during a vacation unless they are going somewhere where there are no dive shops. (But then you will also need to take your own compressor :11: )

If you want more gas for your local diving, get steel tanks as people have suggested. The advantage of an aluminum tank over a steel tank is that they are much much cheaper, and the AL100 does not have that advantage.