Buoyancy in 7 mil and how to be a good instabuddy -- kelp!

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I'm 5'9" 190 lbs and I used to wear 28lbs w. a steel 100 when I dove my 7mm AquaLock. That kind of weight requirement is not at all uncommon around here. In fact, a local day boat suggest 10% of your weight plus 7 lbs when trying to guesstimate weight requirements.

It varies a lot. Boats and shops tend to recommend a lot of weight but it's always seemed insane to me. I'm 5'11" and 190lbs, also using an hp100 and a 7mm AquaLock, but I only need 10lbs (including my backplate!), although my fins are 2lbs negative, I have a light, etc. Still, it's nowhere near​ 28lbs. YMMV.
 
28 lbs is way too much weight. I am 5'4" and 175 and dive a steel 95 and usually go with 16-18 lbs. Once you get to 30 ft the wetsuit is going to conpress a lot and you will sink like a stone so be prepared to hit the inflator button with a couple quick bursts around 30 ft. The trick is to have just enough weight so you don't bob to the top like a cork at the end of your dive when you do your safety stop. The steel tank helps a lot there too. As far as the kelp it looks like a forest under water and is easy to pick a path through. Try and surface on the boat side of the kelp at the end so you don't have to belly crawl over it. If you do get tangled don't thrash around it acts like a rubber band. Simply reach back and snap it in half. You will love the kelp forests it is great diving and a lot of fun!!!
 
Just do a "proper" weight check on the surface before your dive.
 
My experience seems to be the same as others. I dive with 18 lbs of weight when I'm diving my 7mm and a BCD. When I switched to a back plate I was able to drop some weight. I would suspect the shop is giving you too much weight because it is better to have too much than too little. If you only need 18 lbs, you can leave 10 lbs on the boat. If you have 18 lbs but need 20 lbs, you could find yourself light at the end of the dive.

That said, when I first started diving in a 7mm (I used to dive 3mm) I found it hard to move in the thing. Because moving around was difficult, I used my air up faster than normal. This might happen to you as well. However, whatever happens, happens. You can do things like stay slightly above everyone else. This will reduce your air consumption. Hopefully enough to compensate for the 7mm wetsuit.

As far as insta-buddies goes, you are already doing what it takes to not be "that guy". The fact you care enough to be asking is all anyone should hope for. Talk to your buddy and work things out. The only bad insta-buddies I have had come in acting like they know everything or that don't seem to care that it is my dive as much as it is their dive. Let your buddy know you aren't used to PSI as well. Hopefully they'll be able to help you out before and during the dive. Also mention that you might try to stay a little shallow because you want to conserve your air. Some buddies might be thrown if you are always above them. They might find it hard to keep track of you. If they are a good buddy this will bug them. Also, if you point out you aren't used to a 7mm wetsuit and cannot move as fast, they can try not to race off on you.

I've not been in kelp, so I cannot help you there. I have heard it is best to just relax and take it easy. I find this is true in general. So long as you take it slow and never panic, diving is relatively easy.
 
Y'all are awesome! Thanks for the tips.

Concerning weight, I'm a big guy with maybe a little too much belly. Diving with no wetsuit in ridiculously warm water and a 200 bar alum. tank, ~12 lbs. was just right. (6 x 800 grams weight). I think that the 28 lbs. is to provide me a margin of error. I'll be paying close attention to the BC 'spitzer'/purge hose, especially as I get close to the surface. Previously I never used it, and on descent, once at about 30 feet, the BCD was empty and I kept it that way until surfacing.

Swimming in kelp? It sounds like making the love to ze sweet, sweet woman; no force and be gentle! ...for the most part....

Buddies? My conceptions and assumptions are based on being a climber for many years and being literally tied to your climbing partner. There are hosts of ramifications that flow from that. Based on my very limited experience I already know that diving buddies are somewhat different in the recreational context (18 - 24 meters). but as with most things in life, communications is paramount.

I'm sure there is more advice I could benefit from.
 
If you are new to California and kelp the water is usually 50-60 degrees. Colder in low 50's during winter and also the deeper you dive. I've heard reports recently water has been unusually warm, just around 60 degrees. In addition to your 7 mm wetsuit you will probably need hood, gloves, and booties.

Not all hoods are the same. Some are more stretchy than others. You should really try different ones on for comfort. My daughter intentionally dives with a hood larger than recommended baecause she can't stand the tight claustrophobic sensation if it is any tighter.

I've also removed my gloves from time to time and water can feel like ice water. Although the temps don't sound too cold your fingers will go numb in few minutes without gloves. 3 mm are most common but I actually prefer a 4 mm thickness since are slightly warmer.

When buying boots take you fins with you, assuming they are pocket style and not full foot. A 5 mm boot is just fine.

I also like to discuss common hand signals with instabuddy divers, especially the critters you might see. There some cool signals for lobster, octopus, and nudibranchs. I also like to discuss how you indicate tank pressure in particular, then quick discussion buddy separation. Can be as innocuous as, "how do you signal 1300 versus 1800 PSI, and what do you want me to do if we get separated."

I did get separated from an instabuddy once who got paired with me and my buddy who happens to be a newbie. We did a swim through some kelp, looked back, saw my buddy but not the instabuddy. We tried back tracking little bit, swam toward and area thought he went, then surfaced. We saw him about 30 yards off. Turn out as we started through some kelp there was bother group of divers near us, one with similar colored yellow fins. He followed wrong set of fins. Once he realized his mistake he couldn't see us a didn't know which direction we had gone so he decided to wait for us on the surface. We didn't really discuss this but surfaced within less than a minute of each other.

As far as your weights, I'm about 140 lbs. I will use between 18-22 lbs. depending on the dive and who I'm with. I tend to go heavier with my daughter and lighter with more experienced divers. General calculation is 10% body weight + 5-7 lbs. that gets you to a ball park but you should do formal weight check prior to your dive. Discuss with your buddy you are new, haven't used a wetsuit that thick, and will be doing weight check before first dive. Try having all your gear set up early just before you arrive dive spot so all you need to do is finish getting hood and gloves on. Then get into your gear and try to be one of first divers into the water. Crew can help you by either giving or taking weights as needed since you should still be next to boat. By the time your buddy gets in you should be close to finishing weight check. Better 2 lbs heavy than too light and you can always take off before next dive.
 
I shore dove last weekend. Water is really warm right now. My comp said 70 at the surface (confirmed with 2 others), 68 to 25 feet, then 63 to 40 ft.

Good point about hand signals and separation.



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Much depends on the state of the 7mm wetsuit you end up using. My older ones have relatively little buoyancy left (especially the ones with the gaping holes in them) but my newer ones could bob me like a cork The general rule of thumb we use out here is 10% of your body weight plus 5-7 lbs for weighting. Take time to do a buoyancy check on your first dive.
 
Much depends on the state of the 7mm wetsuit you end up using. My older ones have relatively little buoyancy left (especially the ones with the gaping holes in them) but my newer ones could bob me like a cork The general rule of thumb we use out here is 10% of your body weight plus 5-7 lbs for weighting. Take time to do a buoyancy check on your first dive.

Wow. I'm a complete newbie having only just qualified, but the above surprised me! Let me illustrate (in metric!)

I'm 6'1/2", 120kg's, probably 20kg's overweight and was diving with a 12l steel tank and 5mm wetsuit (full body), no hood or booties and jacket BC. I was carrying 7kg on the belt, no weights in the BC and I definitely thought I was over weighted.

The recommendation above would double my weights, wouldn't it? I can't even imagine what that would be like!! The DM & instructor I was diving with were each carrying 1kg only and actually were of the opinion that a good diver shouldn't need weights!
 
https://www.shearwater.com/products/swift/

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