i know diatoms are ugly and a pain but how long do they really last...i know grins said they look like they are going away but that was just cause my powerhead was blowing the sand around but i moved it up a little and where the powerhead isnt blowing ne more the diatoms came back....according to my records they started blooming the 15th but was first noticed the 10th...how much longer do i gotta wait? they are so so so ugly and it makes my tank look dirty (so if i get a room inspection and they see that it could be a write up....yup incentive to clean the tank) is there nething i can do to get rid of em?..i read something about diatom filters? are they cheap? and worth it?