I see you don't have any Grass or an Electric type. There are two ways to pass through this gym. Either catch a Budew and train it or teach Grass Knot to Prinplup.
Grass Knot is the only TM available before Pastoria Gym. But this move is only enough to take out Wake.
- Gyarados, being 237 Kg, gets hit with 120 BP. (I recommend finishing this 'mon with a powerful physical attacker rather than Prinplup)
- Quagsire, being 75 Kg, gets hit with 80 BP and is 4x Super Effective.
- Floatzel, being 34 Kg, gets hit with 60 BP and is 2x Super Effective.
The main Disadvantage with Grass knot is Prinplup is slow and it has to be bulky to face powerful hits. So it is not reliable. The best thing you can do is to catch a Budew and Evolve it to Roselia / Roserade as soon as you can to make job simple.
Also, this team faces a main disadvantage. It cannot withstand Ground E4 (three of your 'mons are weak to ground), so I recommend replacing any one of them (I suppose Bronzor or Skorupi, included Bronzor because it isn't useful to gyms except Snowpoint, where Empoleon could handle) with Roserade. Also, your team needs a flyer (Gliscor can't learn Fly) such as Staraptor, Crobat etc (you will face serious difficulty to go from one place to another). So the sixth spot is also filled.
Hope this helps.