[Solved] Boids - how to change direction?

I’m working on an underwater game and love the new boids behavior! But I can’t figure out how to make them change directions when colliding with a group of tiles. “Avoid object” doesn’t work for some reason - have tried it using the group and also for all the separate tiles.
The fish should turn around and move in the opposite direction of the tile they collided with.

Update - just found a temporary solution: created an invisible object in the center of the area where the fish should swim, on collision with a tiles object an object variable for the fish changes and they swim to the center using “move towards an object”. On collision with center the variable changes back and the normal boid behavior resumes.