I wouldn't call myself a beginner, however, I'm new to wearing a wetsuit. In fact, I now have three suits - one .5mm full body suit, one 3.2mm full body suit, and one two piece (with integrated hood) 3mm open cell suit. Some days I'm struggling to get off the surface and have to swim to the bottom; this obviously uses up a lot of air in the process. Other days, I can get down but notice that I really have to kick to get back to the surface. I am still positively bouyant on the surface. With the two piece suit I've had up to 20lbs. on my belt. As we move into the winter season I've been trying to find the most comfortable wetsuit for the conditions. Water temperature is about 77 degrees right now and I've heard that it will drop another 10 degrees in the next month. The two piece is too warm right now so I'm using the one piece 3.2mm suit with a separate hood. But with all the changes, I'm finding it hard to come up with the right weight combination. Also, I'm not sure how to determine where I become negatively bouyant. My guess is that the deepest I've routinely gone is about 45 feet. Is there any technique for properly determining the proper amount of weight? Also, at what depth should I become negatively bouyant? I've heard 15 feet. Thanks in advance! Magnum166