Low hot water volume in a apartment that I just rented 2 days ago. It has a individual gas heater tank that’s located in a closet. All the pipes are open all the way cold water leading to and hot water Leading out of the unit. Looks like low volume in the whole app. But it’s the worst in the bathtub it’s so low that I cant redirect the water to go true the shower.

Is there any thing that I can do ???