A typical 5' bathtub holds 42 gallons if it's filled to the overflow drain. However with a person in it and not completely full, an average bath takes 20 to 25 gallons.
A typical washing machine on Large Load setting uses 40 gallons per load, but that is spread over two cycles, wash and rinse, of 20 gallons each. On Normal Load it only uses about 16 gallons per cycle.
However, since these devises are a long way away from the tank and the pipes between are very shallow slope the water sort of trickles in.
Put a 4" line right into the primary chamber and let loose 100 gallons and your asking for problems.