I'm having a problem with my pool equipment. The pump attempts to start in the morning as scheduled but is unsuccessful. The pump starts humming and then the circuit breaker flips. If I flip it back on it hums for a second and then starts. There is no air collecting within the pre-pump filter chamber. I tried one morning to bypass my filter and the pump did the same thing. Any ideas? I think my filter canister (which is 15 years old) is worn out and it does have a visible small leak on the side. My thought is that this small hole allows some air to enter the system and I have a small vapor lock every morning. I think it is collecting in the pipe between the filter and the pump and that is why it still didn't work when the filter was bypassed. Sound reasonable?

Anyway, another question: what is a reasonable pump and cartridge filter for a 12,000 gallon pool?