Hot take: that cheap surface marker buoy trick from an old guy in Port Fourchon actually works
I always figured the homemade SMB setup this retired diver showed me at a dock in Port Fourchon was just old timer nonsense. He used a 2 liter bottle, a brass fitting, and about 6 feet of paracord, said it saved him on a job in 40 foot of murky water off Grand Isle. Tried it on a pipeline inspection gig last week and dang if it didn't hold steady in a 2 knot current when my store bought one kept dragging. Anyone else running homemade gear like this or am I late to the party?
What kind of brass fitting did he use on that bottle setup? In my experience the fitting is the whole ballgame, I ran something close to this with a tire valve and a hose clamp and it held fine in maybe 1.5 knots but started leaking past that. Your mileage may vary depending on how deep you run it, but the old timers around the Gulf were onto something with simple gear that you can fix on the boat.