Bird died in hot tub.. what steps/products should I use?

Went to get in my hot tub last night (Saluspa) and discovered that a bird had unfortunately gotten itself in there and died within the last day or two. Going to drain the water completely, but looking for advice on what steps to take and what products to use to completely disinfect it. The filter was on, so all of that gross water has now gone through the system. Thanks in advance!