You can take a bus from Tampa to Ruskin via Westfield Brandon Mall in around 2 h 14 min.
How to get from Tampa to Ruskin
From Jackson St @ Marion St line 360 bus to Westfield Brandon Mall then line 31 bus to US Hwy 41 @ 7th Av NW F/S. 2 h 14 min $2. From Tampa taxi to Ruskin. 27 min $64. From Tampa drive to Ruskin. 27 min $2. From Tampa Uber to Ruskin. 27 min $31.