bro rogersoh,
tks 4 ur encouragement. I still not very sure whether it will actually works or not. Wat I'm guessing is, I might need to drive a powerful return pump to make both suction to works, or else, the bottom suction will not b working at all. I'm right?
As the design is really too simple, even I never c anyone ppl using tat b4, maybe is good tat more experts would like to give ur comments to benefit everyone.
BIG THANK YOU!