sub-tropical drysuit undergarment choice?

[Lorenzoid]

There are a bunch of threads on lightweight drysuit undergarments, but maybe it's better I just ask my specific question. I am relatively new to drysuit diving and have been comfortably diving in 62-73F water in my trilam suit with a Santi BZ 200 (i.e., 200g) thinsulate undersuit and Under Armor wicking baselayer. When the water was 60, and I was fairly still (just practicing skills, for example), I got very slightly chilly in this configuration. Now that the weather is heating up, if I want to continue drysuit diving, what do people recommend for, say, 74-78F water? I think the 200 g undersuit will be too warm, especially if I am more active. Is 4th Element Xerotherm any less insulating than the Santi BZ 200? Comments in previous threads suggest generic polarfleece sweats and/or a medium-weight base layer from somewhere like REI or Cabelas. @tbone1004 the textile engineer has said that polyester is polyester, so why pay for a drysuit brand name.

 

[Marie13]

The Fourth Element Xerotherm is pretty thin. I was chilly in 60F water with it in a trilam suit. I'd consider it good for warmer water.

I wore it by itself, no other layers.

 

[guruboy]

I recently switched from a bz200 to some under armour base layer 2.0 or 1.0

 

[WetRocks]

I comfortably wear my bz200 in North FL caves (68F) and Mexico cenotes, switching to a much thinner hood in the warmer waters.

 

[Lorenzoid]

I recently switched from a bz200 to some under armour base layer 2.0 or 1.0

What water temp? Knowing that in the BZ200 I can get slightly chilled in 60F water if not exerting myself, do you think UnderArmor base layer 2.0 would be enough for me in 75F water? I'm thinking it may not be quite enough for me.

 

[guruboy]

What water temp? Knowing that in the BZ200 I can get slightly chilled in 60F water if not exerting myself, do you think UnderArmor base layer 2.0 would be enough for me in 75F water? I'm thinking it may not be quite enough for me.

in about 70F water. I was starting to get warm in the BZ200 at 70F.

 

[Lorenzoid]

I comfortably wear my bz200 in North FL caves (68F) and Mexico cenotes, switching to a much thinner hood in the warmer waters.

Interesting. It's perfect for 68F, but the cenotes are like 77F. I would think it would be too warm.

 

[Andrew Donn]

I recently dove my suit in warmer water and I just went with my base layer, no actual undergarment. On one dive where the water temp was slightly cooler I threw on a polyester vest and was comfortable.

 

[lexvil]

Shorts and a tee shirt but there is no way I would seal myself up in a airtight bag for water that warm, I would at most use a 3mil for the lower 70's and 1 mil at the upper range.

 

[Rainer]

Shorts and a tee shirt but there is no way I would seal myself up in a airtight bag for water that warm, I would at most use a 3mil for the lower 70's and 1 mil at the upper range.

My wife and I have done four warm-water (~80F) trips in the past few years. We'd freeze wearing what you do in those temps.

For the first two (Utila / Roatan), we took our drysuits and used some mid-weight capilene / fleece undergarments (just go to REI / similar outdoor shop and find something for hiking, no need for scuba specific undergarments for these temps). Perfectly comfortable in the water, a bit warm on the surface (we'd pull the suits down to our waists and remove the undergarment top during surface intervals). For the last two trips (Great Barrier Reef / Bonaire), we've taken 5mm wetsuits. Pretty comfortable in the water, but a bit chilled at the end of the Bonaire trip (6 days, 3-4 dives / day).

For anything <75F, I'd strongly prefer the drysuits, though they are a bit more work / pain to travel with.