Seadebbie

I have shot with a Sony HC9 in a Gates Housing and am now using a Sony XR550v in a Gates Housing. I have always used the appropriate color correcting lens for fresh or salt water. I have had trouble in the past getting white balance below 40 feet using ambient light. I prefer to shoot ambient light. I have been able to fix white balance in post but wish I could get it closer to right when shooting. My husband found something on this forum a year ago or so about setting the white balance on brown sponges in the ocean. Any help or suggestions would be greatly appreciated. I am going on vacation next week on the M/Y Carib Dancer in the Bahamas and would like to try some of your suggested techniques and then let you know the results.
Keep Blowing Bubbles,
SeaDebbie