My pontoons seem to take on about 1/2 gallon water in each pontoon after a days use in the lake. I have thread tape on the screws on the back of them. Is this normal condensation because of the styrofoam inside or a problem somewhere? Also, It has a 50hp mercury motor and the boat is 24 ft long. What would be the max weght occupancy for passengers? It seems to slow way down w/ 4 adults(average weght individuals)