ew 5mm suit, weight sound right?

I just got a new cressi 5mm suit, no more layering 2-3 suits this winter.. here smy math on weighting
body weight 185 10% for 5mm suit = 18.5
3lbs for gloves boots hoody = 3
al80 tank = 5
total 26.5lbs
my plate is 7lbs
new total weight to wear 19.5lbs
so I should start with 20lbs? right
btw im 6ft, very little body fat and i'll be in saltwater 55-60 degrees
thanks
mike b

I suggest you use 20lbs as a strting point and adjust as needed. you'll probably find that over time you'll need less weight. Hope this helps.

best thing for you to do is a proper weight check. Other than that, it's all guess-work and even if we had the exact same body weight and height might not have the same weight requirements, though it would probably be very close.

As example, I wear 14mm on my core, 5mm hands and head, 7mm feet, 10mm arms, 3mm legs in our fresh water quarry (I understand your dislike of layering suits): I wear 16 pounds with a 6 pound plate and an AL80. (40-50 degree water, usually)
In 70+ salt water I wear a 4/3 or 3mm and wear about 2 pounds. In 70+ fresh water with same exposure protection I don't have weights. In 60-70ish salt water with 4/3 and 5/3 hooded vest, I would wear about 4-6 pounds.

For me, the 10% of body weight is always ridiculously high. I'm 6'1, 170 with about 3% body fat and am a bit negative naturally.

for 5 mm about 6-8% total body weight + 3-5 lbs. At 185 lbs total body weight rounding up 15 + 5 = 20 lbs to start. Caveat is a formal weight check is only true way to know exactly if that is correct.

It is best to do a weight check.

If you do it at the beginning of the dive find your proper weight and then add 5lbs. So 20lbs + 5 = 25lbs total.

At the end of your dive do another weight check which should give the correct weight on an empty tank with saturated gear. Make sure to empty your bladder and the tank is around 500psi.

Add a couple lbs when done. Everyone likes to be accurate but as a new diver its best to err on the side of heavy. It's necessary to be able to hold a 15' stop. If you can not, skip the stop and add weight for the next dive.

Remember to add 5-6lbs for salt water. If you do the weight check in salt water you are good to go assuming you're diving salt.

Weight checks are not difficult but if you trap air in your BC it will expand as you rise and before you know it you are rocketing to the surface.