I'd discourage you from training statics in depth. The purpose of static training is pushing into your physiological limits, increasing your hypercapnic and hypoxic tolerance, accustoming to contractions, learning to relax, and to read your own body signals in different phases of the apnea. You can rarely do it safely in depth, even if it is just a few meters, and even if buddy is watching. The buddy cannot be in direct contact, may get easily distracted, and in case you get in troubles, the help may come late.
The best way to practices static training is in a shallow pool for kids. Lay on the surface face down - this position allows you to relax perfectly. Have your buddy clicking your hand (or taping your shoulder) regularly (every couple of seconds) and pulling you out immediately when you fail to respond to a repeated signal.
Here on DB, we hear regularly about fatal accidents of freedivers training at the bottom of the pool. Often they asked someone to keep an eye on them, but as we see it did not help. I remember for example the case of a Swedish freediver who dies in this way. He notified the pool life guard, but the help came too late for him after they noticed he was not surfacing too long:
http://forums.deeperblue.net/safety/...ws-sweden.html