Equal Opportunity
Move SpongeBob along the first red path, then Patrick along the second in order to trap the three yellow Frogfish behind the steel box. Now move Patrick to the purple "X" and have SpongeBob move the wood box along the purple arrow to trap the purple Frogfish.
Now Patrick needs to pop the beachball marked with an "X". SpongeBob can use the other two to build a bridge to the Bonus Bubble. Patrick can then finish the level by building a bridge using the two steel boxes to the Krabby Patties.