Nutrient sampling continues at an active pace. The currents were quite strong this morning and brought with them poor visibility and long streams of large red seaweed blades "blowing" in from offshore. We could tell that the sea above was equally rough because each passing wave increased the air pressure inside Aquarius, squeezing our ears like when the cabin of an airplane is pressurized, except about fives times every minute.

Between morning and afternoon dive excursions, we celebrated Hannah's birthday. Cyd and Emina, our tireless surface support divers, brought down a strawberry Cheesecake (flattens out less than other cakes under pressure) and we sang Happy Birthday with operatic chipmunk voices.

Tonight, we have figured out a dive rotation for tomorrow that will allow the four of us, plus one of the Aquarius technicians to be on the reef nearly continuously for a 24 hour period - collecting hourly nutrient samples. Even though saturation diving allows for extremely long dive times, there are still limits to our allowable bottom times that we have to follow. On the first dive of the day at the deeper site (105-ft / 32-m), we are limited to 4 hours and 13 minutes total dive time. After a 4 hr break, we get half that much time again - 2 hours and 6 minutes. After that, a 12 hour break is required before we can dive again to depths greater than Aquarius hatch depth (about 48 feet, depending on the tidal cycle). Working out a plan to cover a long continuous period, while giving each diver sufficient time out of the water, and also determining who gets to sample the wee hours on the late and early ends of the 24 hour cycle, has made for a lively, but also jovial, extended dinner conversation. Imagine all those great, great film scenes of Cousteau's teams going over dive plans around their galley table, subtract the French accents, red knit stocking caps, and red wine, and you've pretty much got it - or so we'd like to think.