I'm using the Herbie method on my 180 with one internal overflow. The main return is 1.5" and the emergency is 1". I notice a fluctuation in the water level inside the overflow; in the morning the level in the overflow is right at the point where the emergency pipe starts, when I get home from work the water level inside the overflow is anywhere between 4 and 5" below the morning level. I've read through this thread and found that some were experiencing something similar, but I didn't see any suggestions to fix it. I have tried to raise and lower my emergency pipe length, but the problem continue. I would also like to say that I am using an ATO with float switch in the sump and the sump level does not fluctuate. Any ideas would be greatly appreciated; I love the silence but the inconsistent overflow level is driving me crazy.
Thanks,
Carlos
Thanks,
Carlos