Aquatic Brawler

Aquatic is one of the hardest.

However with this setup I won like 8/10, it was a very good one.
All of your pets will have healing, it might take some time, but you will win most.

[npc=65203] 2 [pet-ability=509], 1 [pet-ability=511], 1 [pet-ability=310].

[npc=18839] 2 [pet-ability=509], 2 [pet-ability=310], 2 [pet-ability=273]

[npc=88300] 1 [pet-ability=118], 1 [pet-ability=574], 1 [pet-ability=404]

I started with [npc=65203], and actually won most by that alone, keep healing and shield up, start with shield, then healing mist... when you see they have 1 stack left, refresh.
At times I got into Crawdad, I rarely used the 3rd pet unless the opposite team had that swap pet ability etc.

Anyways, I found this to be very efficient, and I hope it helps.

Good luck! :)

(Got some inspiration here from Rosqo Pet Battler on YouTube, thank you guy).

Edit: Screwed up an ability link.

Here is a strategy that works for this very difficult brawl. You'll be done in 5 minutes.

1. 
   
2. Rename your first aquatic pet to: AquaticTeam
3. 
   
4. Rename your second pet to: PleaseForfeit
5. 
   
6. Rename your third pet to: MuchAppreciated
7. 
   

BAM done.

This is SERIOUSLY rough. I would recommend waiting for the pet weekly event to do this (since there are tons of people using terrible pets and don't know how to pet battle to save their lives). And even then it's rough.