Struggling with the water at Arvendel

[txmimi]

I'm following the walkthrough to get Petuala and party through the water at Arvendel to drain it. I've done steps 14 and 15 3 times and every time, the grate in step 14 stays locked and the second grate mentioned in step 15 also stays locked. What am I missing?

[Kale]

If I understand where you are correctly, you need to enter the leftside pool and head up until you reach the room with a bunch of different switches, above where you saved the girl. (This is part of Step #15) Once you're in the room with a bunch of switches, there is a gray metal plate on the floor towards the top right part of the screen. Toggle that floor switch specifically.

Once that switch is toggled, head back out of the pool, and enter the other side of the pool. Continue to the top right and onto the second underwater screen. The narrow hallway that was previously blocked off should now be open, so you can now reach and toggle the metal floor switch there. Do so.

You now exit the water again, and enter the left side pool again. The Coelancanthe Scale should now be accessible.

Hopefully that helps.

[txmimi]

I don't know what I was doing wrong, but I did as you suggested and got through as described! Thanks again!