HOB filter killed fish or parasite?

[cmcoker]

*Update ...now that I think any other thing or sign I could think of. Only other weird thing was my scopas tang swam back and forth in the back of the tank and very skittish. Now that sounds like velvet is a possibility. And maybe the coral beauty showed signs after 2 days due to exposure then just broke out.


Idk even know if that is possible maybe??

If I do start a new tank is there any reason. To start w fresh sand/water or am I ok using current if I wait 76 days with no worry?

76 days with no fish should eliminate velvet, ich and, iirc, brooklynella.
They need a fish to complete the lifecycle so will doe off. Corals and inverts (shrimp, snails) can stay in the tank.