Hi there! with some newbie questions(trim)

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I don’t have much else to add except to say that your English is very good and I wish I had some video of my open water dives so I could see how my trim was. I just got my c-card last weekend and my first 2 dives I felt like I was in the same position as you (head high). My second 2 dives I switched to steel tanks but I also put my backplate lower on the tank to shift some weight toward my head to level me out.
 
It's not a complete waste of time to practice trim with rented equipment, however you'll need to make adjustments each time you wear different gear. When you've got your own gear, you won't need to go through the process over and over, and you can get it more precise by making many small changes over several dives.

I have found the key to good trim is to get neutral, and be completely still during the dive. It can be rather difficult to resist the temptation to use your limbs to correct a trim issue but that's a matter of practice as well. The right trim isn't usually much more than moving weight from the BCD pockets or weightbelt to the rear upper pockets of the BCD if they're available, and reducing the amount of weight you carry to the absolute minimum- although sometimes there is a need to carry more. Two examples include dives that are very shallow and perhaps a shark dive where you want to be overweighted so you can plant yourself on the bottom without correcting yourself while sharks are moving all around you.

Best way to get the weight down is to spend some of that extra time at the 3 minute safety stop letting ALL the gas out of your BCD. If you sink a bit, lose a pound or 2 on the next dive. If you start to rapidly sink, then lose 2 or more pounds. Rinse and repeat until you're neutral or just a slight bit negative at the safety stop.

If despite all your efforts you still trim head down, and you can't lower your tank anymore, then consider ankle weights.
 
@CDMac, congrats, hope you had some great dives!
 
Honest officer, I did see a fish in the swimming pool, I did, I did, I did! What is that white jacket with the extra long sleeves for anyway? :jail:
 
Welcome. You're fighting far too much heads up trim to fix by moving your legs/head/butt. You need to shift some lead.

"Some weights in hand" trim exercise:
An exercise to do is take some of the weight from your belt and hold them in your hands.
You can still manipulate your inflator valve/mask/regs by putting all the 'hand' weights in one hand temporarily.
Descend in the pool
Extend the weights out in front of you and play with how far in front you hold them, (chest, shoulder, head, full arm length in front).
You should find a point where your body can be very level and in trim with little corrective effort from your legs.
Then hold it there while you play with your frog kick to move you about a bit.
This should give you a better idea of how little effort can be required to stay in trim, and how much weight you need to shift how much higher.
Typically, in trim feels a bit head down to the diver.

I have no connection to UTD, but their Scuba makeover videos demonstrate this trim exercise, though before putting the BC on. You could always do it sans BC by floating the BC above you.

Now you know what an in-trim weight distribution feels like. Doing a normal dive with weights in your hands is not very practical so some location needs to be found on your gear. Achieving that with what ever BC and weights you have on hand is a separate step that gets into details of what you have to work with. On the tank band moves it up from the waist, as does on the tank valve, but both also move it further behind your back when you are level and increase your tendency to roll belly up. On the top curve of the shoulder straps is fairly ideal for affecting weight distribution (it's almost as high as it can go and is inline with your body front-to-back) but can clutter up that area and is often hard to attach there with a jacket BC.
 
Hi! Here's some update. It's so kind of you guys! Thanks for your advice.
I read your replies and did some practice to feel the neutral buoyancy, breathing control, and weight shifts without movement at the bottom of the pool. I moved the weight belt slightly up too. And It worked immediately. It gave me so much confidence to continue practice.
In the clip I was more focused on breathing. Still kind of weird position it was. But I'm happy that I finally found some idea to practice it.
 
Very cool! Knew you could do it! Now, straighten out those legs and dive, dive, dive..... M
 
https://www.shearwater.com/products/perdix-ai/

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