Billy, the magenta hue of the water comes from your MWB. If I remember correctly the WB sensor on the DVX100 is outside and not TTL. Or is that the HVX200? Anyhow, in post, I suggest you boost saturation and color grade back some blue into the water. You can use 3way in FCP or for more control Color. Looks to me a lot of your WB went to yellow instead of red/orange. You may want to dial that back in. It is also important to try get the sequences to at least be close in color.
Was your optical stabilizer on? If you look at 1.55-2.200, the bubbles on your lens jumps quite a bit and that's usually the OS at work.
I liked the turtle with folded fins... cool find. What was that octopus doing on your lens?
Hey Drew thanks for the critique, you've got a good eye. I was white balancing with a filter and I don't know exactly how that affects everything else.
As far as color grading goes I used the program Color for everything. It's much more powerful than the 3-way. If you haven't used it I highly suggest you give it a spin. The interface is kind of intimidating but once you figure it out(buy a book) you can do amazing things with it. Here's a before and after of one of my shots. This was a fairly complicated grade because I added 3 vignettes in order to remove the purple from the background on top of the primary grading.


I kept the color different on the sequences as a hint that they were different dives, it sounds like it came across as a continuity error though. Here are a few screenshots of what color looks like:


The image stabilizer was on but what you're seeing with the bubbles is actually the image stabilizer I used in post. Thanks for the help and if you've got anything else I'm listening.
BTW the octo was put on my lens by a buddy. I turned to film this big valley, turned back and he threw it on my port. I'm not a big fan of that type of thing but thought it looked cool to see it's suckers. I hope it doesn't offend anyone.
Billy