How long ago did your fish die from ich? Do you have any other fish left in the tank? If so, you will need to QT
the remaining fish and leave the main tank fallow for 6-8 weeks. This is the only way to truly get rid of the parasite. UV
sterilizers typically have too high a flow rate to kill the parasite but it will kill off a lot of bacteria. The usefulness of UV
sterilizers is debated often on here.
When you QT
your fish you can treat them with either hyposalinity or Cuppramine. Either are effective. Do NOT remove any inverts as they will die from either of these treatments and are not hosts to ich. HTH