12 volt water punp

[coogs6]

Hi all,
This is my first posting, so I hope I do all this correctly!
I have 2010 Starcraft and I am having a couple of problems with the 12 volt water punp. I only have a problem when the water tanks are not completely full. I am finding that the water pressure from the taps drops as the tanks get lower,also when the tanks get very low the pump takes longer to switch off and sometimes won't swich off at all. I can't find any air leaks and I am finding it hard to understand why the problem only arises when the tanks are not full.
I would really appreciate it if someone out there could help.
Regards,
Graeme

[Farmer Dave]

Sounds like your suction hose that goes in your fresh water tank has a hole in it.