This must be the week for aquarium trials. The Aqueon 56 gallon column tank has rim of about 1 and half inches. I have my HOB overflow box adjusted so that the water is about an inch below the top but still above the bottom of the rim. However yesterday I noticed that the water was higher and only about a quarter of an inch below the top. Probably when I moved the return pump into the refugium, the head pressure was lessened so the flow is slightly higher thus raising the water level in the display. I am not comfortable with the water being that close to the top of the tank so I decided to adjust the plastic bolts and wing nuts to slide the inside part of the overflow box down a little. Unfortunately, my HOB eshopps overflow box is old and one of the bolts snapped off, uhhg!
So off to Lowes I went to see if I could replace it. It seemed that fate smiled upon me in this instant because Lowes did have a plastic bolt that was the correct size. As an added bonus, while I was replacing it, I removed the U-tube that was totally algae covered on the inside and cleaned it with a bottle brush. Now I can see how much flow is going through the U-tube and make sure that bubble build up is not creating a risk of losing the prime in the U-tube. The really great news is that the slightly more flow through the system is a perfect match for the overflow box. No bubbles at all build up but it's not so much that the drain makes a flushing noise. So, at the moment everything seems to be running like a well oiled machine....at this moment, LOL