yazid told me and i also read the manual confirming that the water level by right shouldn't be in the foam tower itself....it should be at most level to the base of the foam tower...
i noticed that when i try to push the water level to middle of the foam tower, the bubbling becomes less vigourous, meaning less air went into the skimmer..but when i lowered the water level, the intense bubbling came back again...
hehe