venting

[pinner_28]

i'm at a total lose i'm had a total creash last year after getting back from a trip.I've been keeping the tank going without livestock for the last year so finally after checking all my paramiters i gave in to my kids request for a few fish .Got a few yesterday and last half within a few hours and lost my last one within 16 hrs i'm ata total lose.Could there be somthing in my sand or rock that is killing the fish i checked everthhing again after the loses and they still seem ok.