mebbe matthew stole your water-
have you checked to make sure you have no tank leakage...
have you checked to make sure they are filled now
have you checked your breaker switch
have you checked your pump and connections(electricity)
have you checked all waterlines for properly tightened hoseclamps and integrity of lines
ok now go back
start over and do not forget to check your bilge
for water in the process.
helpful hint--when filling tanks make sure water in boat is running so pump maintains prime.
could be an air bubble in your pump oops had that
could be........and yes i have had em all ... my boat 40 yrs old.