Baytril is banned for chickens, due to developing bacterial resistant bacteria. But some vets do still prescribe it for serious infections. As long as you know that, the Baytril probably would be a better antibiotic to use.
Some people who do a lot of draining have recommended an 18 or even 16 gauge needle, since the fluid can be viscous. I used what I had last year on my bantam hen, a 22 gauge, and even that worked well. I removed the needle and she did continue to drip as well. You may not be able to prevent that. I had to drain her once every 3-5 days. She died after the third attempt, and the fluid had become thicker and cloudy, signs of infection. It
Draining prolonged her life about 2 extra weeks and made it easier for her to breathe from having a bloated lower belly, but I’m not always sure that it is that beneficial. I tend to let nature take it’s course with my chickens.