My overflow (Herbie style) was slurping air from the main siphon drain. I was being lazy because its summer time and I have been outside and neglecting my tank, so I did not adjust the overflow to balance it. I noticed that after a few days of the full siphon slurping air and water, my water clarity improved. My water always had a cloudiness to it but it turned gin clear. I also noticed that my pH had risen from a high of 8.12 (normal siphon) to 8.26 (slurping air). I normally hate the sound of a loud overflow but now I am letting it suck air. All the corals seemed to respond positively as well. I haven’t made any other changes to the system.
I am wondering if with a herbie style overflow, the oil film that forms on the surface doesn’t get sucked in the overflow plumbing. The main siphon is below the surface and the durso is also pulling from below the surface. I have good surface agitation in the tank but still see oil sheen in some areas that didn’t seem to break up. Was this oil sheen going over the weir and sitting in the still overflow box? With the full siphon sucking water and air, it is truly skimming from the surface now.
I have tuned the full siphon to just be slurping a slight amount of air and I made a cover for the overflow. This has quieted thing down a lot. Its still audible but I don’t even pick up on it any more.
For now, I will keep my overflow slurping away. Maybe one day I will re tune the overflow and see if my tank goes back to being slightly cloudy and lower ph.
I am wondering if with a herbie style overflow, the oil film that forms on the surface doesn’t get sucked in the overflow plumbing. The main siphon is below the surface and the durso is also pulling from below the surface. I have good surface agitation in the tank but still see oil sheen in some areas that didn’t seem to break up. Was this oil sheen going over the weir and sitting in the still overflow box? With the full siphon sucking water and air, it is truly skimming from the surface now.
I have tuned the full siphon to just be slurping a slight amount of air and I made a cover for the overflow. This has quieted thing down a lot. Its still audible but I don’t even pick up on it any more.
For now, I will keep my overflow slurping away. Maybe one day I will re tune the overflow and see if my tank goes back to being slightly cloudy and lower ph.
