Transfilling Tank To Tank

[Alan Garrett]

I have also used a transfill whip to equalize tanks with my buddy before a dive in Roubidoux, which is a remote cave as far as gas fills are concerned. I was diving double 80's and he was diving 104's (I think, maybe a little smaller) and I didn't have enough gas for the next dive. We were about an hour from an air fill station and over 2 1/2 hours from the nearest Nitrox, so the whip came in handy for "siphoning his gas tank" and getting another dive in. -Alan

[caveman21]

I'm wondering about something. In what situations would you every want to have a transfill whip with you in the field to transfill gasses from one tank (or set of doubles) to another? I'm confused about the applicability of this and why you'd do it. I know you could do a top off, but wouldn't that assume the supply tank(s) were large enough to manage a top off without requiring your fill tank(s) to be drained?

The transfill whip I have gets used very frequently, especially when I do a lot of river diving for fossils etc. My river kit consists of a 30cf tank mounted on a plastic backplate, no bc. I prefer the small tank for shallow, swift current dives as it creates much less drag than a regular sized tank and bc. I stay on the bottom until out of gas, go back to the canoe, fill off of a jacked up set of doubles, repeat until worn out. The whip also gets uses for out of the way sidemount dives in much the same way. Do a dive, top off tanks from doubles, do another dive.

One thing I did to my whip that made it infinitely more useful it use high pressure hydraulic quick disconnects between the hose and the fittings. This allows me to use the same fittings with a pressure guage, make my whip a din to yoke, din to din, yoke to yoke, o2 to yoke ect. just by changing out one or both fittings. The hose has female connectors on both ends and the fittings have the male connectors. Good stuff.