Pool Pump tripping circut

[Ramsyanks3]

Hello,

Please forgive me if this is in the wrong area. I opened my pool yesterday and when the pump ran for 15 minutes it tripped the circut (Using GFCI plug and timer box to turn on. I reset the GFCI and it happened multiple times. I unplug the GFCI cord that was directly into the GFCI outlet and used a portable GFCI into the regular outlet (Not timer Box) within the same GFCI outlet and the pool pump runs with no problem. What is weird the pool pump is running with the portable GFC cord and the circut is off in the basement. How is this possible? Is this dangerous? Sorry if this is confusion. Any help is appreciated.