Flightlead
Contributor
as far as markers go, I reckon that 1/2 gal milk jugs will do, perhaps with a number painted on in hi viz. paint. no sense in using expensive lift/marker bags. each team of two divers could easily take a half dozen. just fill 'em with water at the beginning of the dive and they are neutrally bouyant. attach a line to what you are marking and to the milk jug, add a shot of air, hey presto.