You might want to check your equipment. If your 'my tanks' is correct and the fact that you lost the clowns then that leaves you with 1 fish, correct.. the 2 clowns you had for 5 days... so one would suspect that the issue may be in the maintenance/equipment area.
what are u using for filtration? HOB
, Canister, sump? Using a filter sock?
How many powerheads?
Did you cycle/cure the rock in tank? How long ago?
When you say everything else in the tank is fine; inverts/fish... Isn't that 1 fish at this point? 3 total, 2 died?