i think my 2 clownfish have velvet disease help??

well my last clown died this morning.i brought some invert safe treatment yesterday but i was too late, but i could not find him so my cleaner shrimp must have ate him.well i am pretty sure they had velvet disease so im going to leave the tank fishless with just the 2 cleaner shrimp and hermits for about 8-10 weeks so that the parasite hopefully can die off then i will purchase another clown and go from there.its all my fault if i never left my filter hose with out the right part they would have never got sucked in and could still be here now,but lesson learned.as my tank is just over 1 month old leaving it 8-10 weeks fishless will be good for the tank wont it???

as i only have the 2 hermits and 2 shrimp when and how much water shall i change??
originally before the clowns died i done 10% every week-2 weeks sometimes.

 

it was for sure not velvet i had it and lost 100% of my fish to it about a year ago. and you can tell velvet by the fish getting cover in a white film and then there gills close up and they die. its not a nice thing at all:-[. sorry about your loses:-[