livewell issue

[pair of jacks]

The newer SeaCraft's have the in-deck livewells in the stern. Here's my question: does anybody elses livewell fill with sea water thru the overflow outlet ? Mine does and I don't know why or how since the water has to travel up to do this. I can leave the dock perfectly dry, fish or cruise for a bit and the live well is at least half filled. Its just annoying, nothing major but I don't know why. Anybody else with a 21 that has this issue ? By the way, my previous post about my Optimax problem has been resolved- turns out it was a combination of a coil and the poppet valve which I never heard of but apparently when defective causes water to be pumped into the cowling . Running great again.