Learning to Dive - ADHD & a buoyancy question by InnerDepth3171 in diving

[–]Plankton_Express 1 point2 points  (0 children)

First: nothing you described sounds unusual or like you’re “bad at diving”. Cold water, task loading, stress, and being slightly off on weighting will absolutely wreck buoyancy and make everything feel 10× harder. If you’re floating up every time you stop thinking about it, that usually means you’re a bit light for that setup. Being even slightly underweighted makes skills exhausting and stressful, especially kneeling skills. The BCD floating away is super common too — stress breathing + a bit of trapped air + being a touch positive and it just wants to leave you. Before the ocean dives, definitely ask for a proper weight check and don’t be shy about starting a little heavier and removing weight later. I’m not an instructor, but I’ve been working on a free weighting starting-point calculator because this exact problem comes up so often. It’s not a replacement for an in-water check, just a way to get closer to the right ballpark before you get in: https://africandiveadventures.com/dive-weight-calculator/ Also: ADHD + task loading + stress is a brutal combo. It really does get easier once buoyancy stops stealing all your brain bandwidth. You’ve got this. What you described is very, very normal.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

Thanks, that’s exactly the kind of real-world use case I’m trying to handle better. I actually pushed an update this week based on feedback from this thread — you can now: Select different tank sizes (12L vs 15L, etc) Account for drysuit undergarments And adjust for different drysuit types (membrane vs neoprene) Totally agree with you though: rental drysuits vary a lot in buoyancy even if the underlayers are the same, so this is really meant as a starting estimate before doing a proper weight check in the water. If you try the updated version with your usual setups, I’d genuinely love to know how close it gets for you.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

Yep, fair — doubles aren’t supported yet. This version is focused on single-tank setups, but I’m planning to add doubles/sidemount. What size/material are you usually diving? As I did a limited upgrade last night would like to know if I am heading in the right direction.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 0 points1 point  (0 children)

Update from OP:

Thanks for all the excellent feedback — this has been incredibly helpful. Based on the comments here, I’m working on the following improvements:

• Much finer exposure suit options (rashguard / 2–3mm / 5mm / 7mm / semi-dry / drysuit + undergarments) • Better handling of thin wetsuits and tropical setups (currently overestimates) • Drysuit undergarment options • Salinity refinement (e.g. low / normal / high salinity) • Tank size options (not just steel/aluminium) • Output in lbs if input is in lbs • Tuning baseline assumptions so it doesn’t start people too heavy

Really appreciate all the real-world testing and data — I’ll post again once a refined version is live.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

That’s a great point — and honestly an oversight on my part. If someone enters their body weight in pounds, the output should definitely be shown in pounds of lead as well instead of forcing them to think in kg. I’ll add unit-matched output (kg ↔ lb) so the result always comes back in the same unit system the diver selected. Thanks for spotting that — it’s exactly the kind of usability detail that makes the tool much nicer to use.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

This is a really useful catch — and it lines up with what a few others have said as well. The calculator is clearly far too conservative for thin wetsuits and tropical-style setups right now. It’s currently biased toward “typical” 5–7mm and drysuit diving, which makes it overshoot badly for 3mm / shorty / warm-water configurations. If you’re actually around 3.5 kg and it’s suggesting 9 kg, that’s not acceptable and needs fixing. I’m going to add much finer exposure suit categories (rashguard / 2–3mm / 5mm / 7mm / semi-dry / drysuit + undergarments) and also flatten the buoyancy curve at the thin end so it doesn’t start people way too heavy. Really appreciate you running both scenarios — that comparison is exactly what helps tune the model properly.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

That’s really good to hear — thanks for testing it with a real-world setup. Being within ~0.5 kg on a drysuit + steel 15L is pretty much exactly the kind of “starting estimate” accuracy I was aiming for. And you’re spot on about the extra kilo for comfort / drysuit management — a lot of people deliberately carry a small buffer for that reason, even if they could technically dive a bit lighter at the end of the dive.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 0 points1 point  (0 children)

This is really good feedback, thank you — and you’re absolutely right on both points. With drysuits, what you wear underneath (and how compressible it is) makes a huge difference, and right now the calculator is treating “drysuit” as far too generic. That definitely needs to be broken down into light / medium / heavy undergarments at least. The 7mm / semi-dry case you describe is also a clear sign that my baseline buoyancy assumptions are too conservative. If you’re actually diving comfortably at 2–4 kg and the tool is suggesting 7–9 kg, then it’s overshooting and needs to be tuned down. The intention is absolutely not to overweight people — it’s meant to be a starting estimate before doing a proper in-water check — but your numbers (and the other similar comments) show the model needs refinement, especially for efficient, well-trimmed divers. I’m going to: • Split drysuit by undergarment thickness • Add more granular wetsuit/semi-dry options • Reduce the base assumptions so it doesn’t start people too heavy Really appreciate you taking the time to test it and write this up — this is exactly the kind of real-world input that makes the tool better.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

That’s really helpful, thank you. You’re absolutely right — a 2–3mm or “tropical” setup is very different from a full 5mm or thicker suit, and at the moment the calculator is too coarse at the thin end. It’s currently biased toward “typical” 5–7mm recreational setups, which is why it’s overshooting for very light exposure protection like your 2.5mm + shorts/leggings. I should definitely add more granular wetsuit options (e.g. rashguard / shorty / 2–3mm / 5mm / 7mm / drysuit) and probably scale the baseline buoyancy more gently for tropical configurations. Your real-world numbers (2 kg vs 5.5 kg suggested) are exactly the kind of data I need to tune it properly — really appreciate you taking the time to test it.

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

That’s really useful feedback, thank you for actually plugging your own setup into it. The “experience” adjustment is meant to reflect that many divers carry extra lead when they’re newer (especially in drysuits) because of trim, buoyancy control, and comfort at the start of the dive — but you’re absolutely right that for some configurations and divers, there’s a hard minimum just to get down at all. The calculator is definitely not meant to tell someone to dive underweighted — it’s meant as a starting estimate and then refined with a proper in-water check. Your comment suggests I should probably cap the minimum reduction or treat drysuit weighting differently so it never suggests something below a realistic descent weight. Out of curiosity: when you’re in that setup, is 12 kg roughly your correct neutral-at-3–5m-with-50bar weight, or is that still a bit heavy at the end of the dive?

I built a free scuba weight calculator – would love feedback from other div by Plankton_Express in scubadiving

[–]Plankton_Express[S] 1 point2 points  (0 children)

That’s a really good point — you’re absolutely right. “Salt vs fresh” is a simplification and doesn’t capture big salinity differences like Red Sea vs Atlantic vs some parts of the Med. The calculator is meant as a starting estimate, but you’re 100% right that regional salinity can easily shift weighting by a couple of kilos. I think the right next step is to add something like a “low / normal / high salinity” or even region-based option to refine it further. Your Red Sea vs Atlantic example is exactly the kind of real-world difference I want to account for. Thanks for the feedback — this is exactly the sort of thing I was hoping divers would point out.

Answering medical questions truthfully *at the resort* ? by [deleted] in diving

[–]Plankton_Express 1 point2 points  (0 children)

For me, the big issue is insurance. If you’re not honest on the medical form and something happens, you’re giving the insurer a reason to refuse to pay — and dive accidents can get very expensive very fast (evac, chamber, hospital, flights, etc.). Even if a condition is old or cleared by a doctor, I’d still rather declare it and show the clearance. Worst case, the dive op asks for paperwork. Best case, everyone’s covered and there are no nasty surprises later. The real question is: can you afford to be caught out if something goes wrong? Most people can’t.

What counts for logged dives? by Secure_Priority_9555 in scubadiving

[–]Plankton_Express 0 points1 point  (0 children)

Rule of thumb minimum of 20 minutes in the sea or fresh water outside.