Do i need to bleach tub after using spray to totally kill fungi in athlete's foot?

No: Topical or oral antifungals will work, but a dilute bleach 1cup to whole tub of water can decrease bacteria and fungi in area. For foot bath a teaspoon of bleach would be appropriate. Dilute clorox anywhere spray inside shoes may decrease chance of recurrence.

Not really.: This would be a solid extra precaution, but not acutely necessary, given that the spray killed it. Consistent washing, and thorough drying are very important, as is changing socks/clothes daily. Use of gyms, etc. Can reintroduce athlete's foot so the above steps are crucial.