Trouble with Clown Knife Jumping

Question
We have had a clown knife for several years now with no problems.  Yesterday he jumped out of his tank.  I have heard of this happening with these fish so I didn't think much of it.  My husband and I had some tank rocks so we put one on each lid to weigh them down.  This morning he was able to bust through the lid and that rock to jump out.  Is there something that would cause this sudden spurt of energy?  What can we do to the tank to keep him from getting out and coming home to find he became a treat for our cats when he came out?

Answer
Dear Amanda,
You didn't mention the size of yours tank and the size of the clown knife, but as you have mention that it is jumping from the tank, it is really needed for you to know that the said fish only dies from making this habit. To prevent the said problem more larger size of tank is highly essential and if it is not possible then you have to cut a little of the pelvic fin of the knife to make him/her forget the habit. Thanks. Good Luck.

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