soap suds

Question
my niece washed one of her toys and put it inside my 200 gallon aquarium, when I noticed what she had done, soap suds were starting to form at the top, and my fish are all at the bottom,2 died, and they are all babies, what can I do to clear my tank without emptying all of the water, and saving my other fishes

Answer
I'm sorry for the problem.  You're not the first person to have something similar happen.  A 200 gallon aquarium is big but not so big that I wouldn't suggest changing the majority of the water.  What fish do you have in there and how big are they?  I suggest at least removing 50% of the water, more if you can.  Be sure to add dechlorinator with the fresh water.  Also, use paper towels to skim what suds you can off the surface.  Add a large mesh bag of fresh activated carbon to the filter to help remove more of the soap.  Change it in 24 hours and repeat that until things improve.  

So, water changes, skimming the surface, and activated carbon are your best bets.

I hope your other fish are okay!