Which fish are you talking about dying? Are you sure that your tank has cycled? I know that some people have cycled theirs in shorter time than the rec. 6 weeks but not sure about 3 weeks. Once the sharks hatch, the clowns will surely die. The sharks won't survive long in that size tank either. What species of sharks are they, do you know? What information have you collected on that species as far as feeding, size, min. tank size, water temp, etc... Are you using the clowns to cycle your tank? What else are you considering adding to the tank?
Have you tested your water and what are the readings?
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