Thanks. I just use a GoPro Black 6.
My dive guide, Ketut Gede Somadyana or "Today" for short, has been guiding me in Bali for over 10 years. This is his dive shop:
aqua cat bali, the best travel to scuba diving / dive / diving in Bali, Indonesia
On the dive at Blue Corner that day, he instructed me to follow him along the wall edge on the left shoulder, at about 60' deep to conserve air & bottom time, while he was cruising at 100' depth in search of Mola Mola. Visibility was excellent at the time, I could see him in the blue, 40' below me. As soon as he saw the Mola Mola, he gave me a signal to get down to his depth. We were ended up at about 137' (42m) by the time the 4 Mola Mola were being cleaned by banner fish. When we were done taking pictures & videos of the Mola Mola and ascent back to the boat, I still had 1000 psig.