Not sure if this is the right place..

So I've recently bought and moved into this 1992 mobile home. The 30 yo water heater was a 19 gallon the new one's a 20. I ripped the floor up and the boards look fine so I was wondering...if I wanted to add extra support what would be the best route? Should I add sister 2xs along the north and south sides then take joists hangers and add a beam along the center making a H? Full disclosure, i have no close as to what I'm doing. Just winging it.