What was wrong with the airline tubing? Just make sure the bucket you're acclimating into is below the tank you're removing water from. It actually takes a pretty tight knot to restrict the flow enough. I tie the knot after the syphon is going.
I just typed this yesterday for another member, so excuse the copying and pasting-
- You need a large clean pitcher, a bucket, and a piece of airline tubing (you can just use the bucket if you want. Make sure it wasn't used for cleaning purposes or has soap residue
- Place the pitcher inside the bucket (to catch overflow)
- Place the fish and the water they're in now into the pitcher ( you can add as many fish as will fit comfortably in the pitcher)
- Start a syphon from the new tank (you can just suck on the end)
- Tie a knot or two in the airline tube so it restricts the flow and you get a slow and steady drip (maybe one drip per second)
- Let the pitcher slowly fill. Once full, dump half the water out of the pitcher and let it refill a second time (you can do this as many times as you want
- After that, pour the water out of the pitcher through your net, and catch the fish then place the fish into the new tank without letting the store water into your tank
- Voila! You've drip acclimated them