Aquariums: Behold my Son, who decided it would be funny to dissappear for 3 weeks

Behold Haku!

About 3 weeks ago we had a tank crash due to some contaminated water (unknown at the time that apartment maintenance had worked on pipes without saying anything and released heavy metals into water) during a water change.

Had to do a 90% water change with some water I aquired from local fish store. During the process we removed everyone from the tank and placed in holding with clean tank while we recycled everything.

Haku was not found and thus counted amongst the fallen.

3 weeks later, I get home from work this morning and who should I see front and center of my tank?

Haku