The most obvious effect the moon has on us is our oceans (high tide and low tide). but when we have high tide where is the water coming from? Does it come from down below at the bottom of the ocean or does it bow out leaving the middle of the ocean lower than the outer sections? It could also be a matter of density. Making the ocean less dense. All these theory’s possibly answered by someone. But imagine.

If the ocean is raised strictly by gravity pulling it up, there is a vast unknown that we have about our planet still. What if there was a whole separate way of life down there and the gravitational pull creates dry bubbles at the bottom of the ocean. It could be a part of the natural order of things down there, like we have day and night they have dry and wet. A reverse tide for a different civilization to emerge out of underground caves.