Recreational Ascent Rate in the last 15 feet

[Hatul]

I try to follow my G2 dive computer that uses a variable ascent rate. From 15 ft up it does 10-20 ft/min as it slows even on the last part of the scent to 10 ft/min. It's really slow and hard to make the effort to take a minute to make that final ascent, but I try.

 

[biggpa]

I just opened the Shearwater Cloud Desktop application - the graph has accent and GF99 (new to me, I dont open cloud desktop that often). Additionally, the "Computer Info" tab has the actual surfacing GF.

Pretty interesting to look at the graphs in context of these accent/SurfGF/GF99 discussions.

 

[eleniel]

I've managed to get it down to about 30fpm (it used to be much faster) recently. It's one of my biggest issues I'm trying to work on with diving and I know it but haven't been able to slow it any further - I usually do my SS around 18-20 feet because once I hit 15 feet I may as well be on the surface. I generally have to do my SS while finning gently down just to keep it in the right range. This is the case regardless of how much air is left in the tank - could be 500 psi, could be 1600 psi, it still happens - no air in the BC at all, not holding my breath, etc. I am just super floaty in shallow water (I have to fin down to about 20 feet after splashing).
Below 20 feet I have no issues hovering at whatever depth, its just the shallow depths I really struggle with. Because of this, if I do any diving deeper than 80 feet I add a SS around 40 feet for 3 or so minutes followed by my 18 foot or so SS for 3-5 minutes.

 

[FreeFlyFreak]

I've managed to get it down to about 30fpm (it used to be much faster) recently. It's one of my biggest issues I'm trying to work on with diving and I know it but haven't been able to slow it any further - I usually do my SS around 18-20 feet because once I hit 15 feet I may as well be on the surface. I generally have to do my SS while finning gently down just to keep it in the right range. This is the case regardless of how much air is left in the tank - could be 500 psi, could be 1600 psi, it still happens - no air in the BC at all, not holding my breath, etc. I am just super floaty in shallow water (I have to fin down to about 20 feet after splashing).
Below 20 feet I have no issues hovering at whatever depth, its just the shallow depths I really struggle with. Because of this, if I do any diving deeper than 80 feet I add a SS around 40 feet for 3 or so minutes followed by my 18 foot or so SS for 3-5 minutes.

Wear more weight.
You shouldn't have to fin down to maintain a 15ft stop. You should be able to easily hold a 15ft stop with minimum gas in your tank.
Personally I like to be able to hold 10ft. I often see a lot of cool stuff in the shallows when shore diving.

 

[eleniel]

Wear more weight.
You shouldn't have to fin down to maintain a 15ft stop. You should be able to easily hold a 15ft stop with minimum gas in your tank.
Personally I like to be able to hold 10ft. I often see a lot of cool stuff in the shallows when shore diving.

I'm sure you're right. I don't like needing to use the bc much at depth so it's just finding that balance that's a challenge. I'm not super experienced so I know it's something that'll come with practice and experimentation - it did get easier when I switched from a 3mm shortie to a 1mm on my last dive trip (but that was drift diving in Cozumel which has its own condition factors - coincidentally, that's where I need to do the most actual work to maintain for the SS - I wonder if it's related to current or surge too). I'm at the point where I don't need any weights in warm fresh water (I can hover around 10 feet forever without effort) but salt + temperature and other various conditions make it more complicated.

 

[Bob DBF]

This is the case regardless of how much air is left in the tank - could be 500 psi, could be 1600 psi, it still happens - no air in the BC at all, not holding my breath, etc. I am just super floaty in shallow water (I have to fin down to about 20 feet after splashing).

If that's the case, you need to add a bit of weight. You might have your buddy check for an air bubble in your BC that wasen't vented. Also you might check dor a slow leak adding air to your BC. It isn't all that likely, but...

A good weight check is to hold the safety stop with an empty BC at 15' with 500# in your tank. Carry some extra weights and hand off the ones you don't need to your buddy at the safety stop.

The only curve ball is if you wear a lot of neoprene, if you check coming back from 130' you will need less weight than if your dive was at 60' because the neoprene won't rebound as much from a deeper dive. It's not a lot but you might notice it. You just mentioned warm water diving so disregard this part.


Bob

 

[eleniel]

If that's the case, you need to add a bit of weight. You might have your buddy check for an air bubble in your BC that wasen't vented. Also you might check dor a slow leak adding air to your BC. It isn't all that likely, but...

A good weight check is to hold the safety stop with an empty BC at 15' with 500# in your tank. Carry some extra weights and hand off the ones you don't need to your buddy at the safety stop.

The only curve ball is if you wear a lot of neoprene, if you check coming back from 130' you will need less weight than if your dive was at 60' because the neoprene won't rebound as much from a deeper dive. It's not a lot but you might notice it. You just mentioned warm water diving so disregard this part.


Bob

Just because I was talking about warm water doesn't mean I don't dive cold too - I certified in cold and more than half my experience is in cold water. I haven't had as pronounced of issues with cold but I'm guessing that's likely because I am adequately weighted when I dive cold. Most of the diving in my area is cold (salt or fresh) so I get a lot more regular practice working with those temperatures and the necessary thermal protection.
I probably should've specified that in my initial post but I was thinking about my recent dive trip and how much work the SS were. The info about the neoprene rebound is good to know and I'm sure it'll be useful. I'm here to absorb as much information as possible.

I actually did have a slow leak with my bc on that last trip - it was slow enough that I wasn't sure if I was imagining it or not when I had to keep venting it periodically at depth (I typically dive with no air in the bc unless I get pretty deep and none of these dives were really that deep) - I assumed maybe I had a little air left in that I hadn't managed to vent out at the start, and that as we slowly ascended during the dive, the volume was just increasing, which is why I kept finding air where there shouldn't have been any. I realized that it was in fact leaking when my bc decided to auto-inflate at depth (I was watching it though because I was really wondering wtf was making me struggle with being too floaty). I didn't rocket to the surface - just vented and disconnected the hose and all was fine - but I wonder if that was contributing to the extra amount of work I was doing.
I'm not saying it was all equipment issues and water conditions, I'm just suddenly wondering if those were contributing factors (I didn't have any issues on the SS for the disconnected hose dive, and we actually hung around 13 feet and watched a really cool eagle ray swim below us. We only did a couple more dives and I got the inflator hose replaced prior to those and the SS was much easier - but I still could've used a couple more pounds I'm sure).

ETA: if I come across as rude, I apologize and do not mean to - I'm actually grateful for advice

 

[chillyinCanada]

(SNIP)

Below 20 feet I have no issues hovering at whatever depth, its just the shallow depths I really struggle with. Because of this, if I do any diving deeper than 80 feet I add a SS around 40 feet for 3 or so minutes followed by my 18 foot or so SS for 3-5 minutes.

I think you'd be better off doing a longer SS at 18 than continuing to load at 40'.

 

[eleniel]

I think you'd be better off doing a longer SS at 18 than continuing to load at 40'.

Yeah I've recently been seeing this. Now that my dives are getting a lot longer I may need to reconsider.

 

[Bob DBF]

I'm not saying it was all equipment issues and water conditions, I'm just suddenly wondering if those were contributing factors (I didn't have any issues on the SS for the disconnected hose dive, and we actually hung around 13 feet and watched a really cool eagle ray swim below us. We only did a couple more dives and I got the inflator hose replaced prior to those and the SS was much easier - but I still could've used a couple more pounds I'm sure).

ETA: if I come across as rude, I apologize and do not mean to - I'm actually grateful for advice

No worries, more information is good. Sorry to assume you were a warm water diver.

Usually the leak is in the inflator itself, a leak in the hose would have reg hose bubbling when not attached. If it changed rather than ended, most likely the inflater mechanism on your BC needs to be cleaned and/or the Schrader valve replaced.


Bob