40 Fathom Grotto Protection

[SlowRain]

I am going to be diving some this April and probably May down at 40 fathom grotto for some classes. Never dove the site before. From what I have been able to pickup from the board, water temps vary there by depth. Classes are going to be deep dive with decompression stops...so a lot of "sitting and waiting".

I have a 5mm Henderson Gold Core (rear zip jumpsuit) but I am thinking from what I read that might not be enough. I don't get chilled that easy. I also have a Bare Xcd2 Drysuit, but the undergarment I have is probably going to be a bit too much.

Amongst all the stuff hanging in my dive closet is a Henderson Polyolefin dive suit that is not neoprene but supposed to be as warm as 2mm. Breathable material..etc etc. I am wondering rather than having to buy something new or run around the dock in some long underwear if using that might be an option and a go between. I really would like an alternative to buying a lighter weight undergarment which I would probably never use anywhere else, and certainly am not going to buy a 7mm suit.

Grotto veterans...give me your opinion.

 

[carlcz]

From my last visit to 40 fathom:

Location Depth(ft) TdegF
40 Fathom Grotto 117 67
40 Fathom Grotto 27 70
40 Fathom Grotto 106 67
40 Fathom Grotto 154 66
40 Fathom Grotto 158 67
40 Fathom Grotto 176 66
40 Fathom Grotto 139 67
40 Fathom Grotto 200 66
40 Fathom Grotto 195 66

 

[SlowRain]

From my last visit to 40 fathom:

Location Depth(ft) TdegF
40 Fathom Grotto 117 67
40 Fathom Grotto 27 70
40 Fathom Grotto 106 67
40 Fathom Grotto 154 66
40 Fathom Grotto 158 67
40 Fathom Grotto 176 66
40 Fathom Grotto 139 67
40 Fathom Grotto 200 66
40 Fathom Grotto 195 66

Yeah that is what I have been reading...the undergarment I have would be fine if I was in water in the 50's but I am thinking I would be par-boiled in it in those temperature ranges. I wouldn't have a problem with 5mm if I was going to be swimming around and active...but I don't think that is going to be the case here. Both sessions I understand we will be in the 200 foot range and looks like from your data this is basically 1 thermocline. Anyone else?

 

[refinished]

In a 5/4, I got pretty chilly @ 160'. I have average tolerance for cold. A hooded vest would have made my life better. The duckweed makes it darker than you would expect with that viz/depth combo - for me, the darkness adds to psychological sense of cold.

On days that I have been there, the thermocline has been at 90-110'

 

[carlcz]

I used a wetsuit -7mil for my dives with a hood. No problems. Dives were in May.

 

[UP4AIR]

I did some training there a year and a half ago. I don't get cold easily, but wore a drysuit due to hang times. I wore my Moby's trilam with some cheap polypropylene (like military style) long johns, the first couple of days. I wore these over a pair of shorts and a t-shirt. The second couple of days I wore a 300 gram fleece,over the same shorts and t-shirt.

The fleece was a bit warm on the surface, but REAL NICE on the hangs. I think you could probobaly pick up some reasonable priced polypro, and layer it with some other undergarments, and be right comfortable.

A couple of the guys I was training with wore wetsuits, and on the second and third days they got cold. I think something to keep in the front of your mind is that required decompression and being cold don't make for a good combination.

 

[SlowRain]

Yeppers...been there done that (decompression and being cold). Thanks for the suggestion...think I know what to do and best of all don't have buy anything!

 

[moneysavr]

Yep the duck weed!
I would think the hangs you would get cold,It is a great site as you get your gear down on the floating docks-kit up and splash so you should not over heat.
I did training years back with a 7mm for deep air and did get cold on the hang-Great traing site Hal has and I felt at home in the dark cool waters!
Brad

 

[Scared Silly]

I wore my DUI CF200 with some midweight capline for my dives and was comfortable. I did not wear a hood. I can not say we did a lot of swimming around either.