Marine velvet

[amdninjaboy]

I've lost most of my fish to what I think is velvet. I thought it was ick at first but by the time I figured it out it was too late. What causes velvet? I was stocking my tank slowly and was up to 5 fish. I had 5 conch snails, 5 turbo snails and 12 nassarius snails. All of them still alive and kicking. Added 2 blood shrimp and 3 peppermint shrimp and the velvet hit about a week later. Can inverts bring velvet with them but not suffer from it?? Just trying to figure out what I did wrong and how I can stop it from happening again.

Thanks,
Shane.

 

[amdninjaboy]

Sorry forgot tank specs..
90 gal tank, 20l sump
Amm-0, trite-0, trates-5,
Ph-8.2, temp-79.5
Protein skimmer, chaeto in sump, 90ish lbs live rock.
All inverts in tank still doin great..