180 Gallon In Wall TankPosted:
April 24 2017 at 3:22pm knowen87 wrote:
Krazie - I took it down lower so that it would not show through the glass on the back of the tank. I am still not sure what I will do for a background. I didn't want to put the sump a lot lower though. I built the sump stand to allow for an additional 40g breeder to fit below.As far as self starting issues, I guess that I am not sure what you are talking about. When the power goes out the overflow box drains and water will just sit in in the drain until the return starts back up. There is no siphoning and it starts up just fine. My main concern is sediment buildup in the line. I will see how it goes. One nice thing is that I do get a lot of flow from the return. The total head height is only like 1.5ft-2ft so the flow rate substantially more than when the sump was under the tank.
Let me use your picture to try and explain what I meant.
So in order for the bean animal to work correctly (and silently) it has to be able to run a restricted siphon on the herbie, a full siphon on the Durso and not draw air into the line from the emergency. When the return shuts off the siphon breaks on both of the siphon drains and fills the pipe with air down to the level of the water in the sump and then holds water in the pipe drain pipe at that level. See my edit of your picture below. (Red is water level with the return off, yellow is air in the pipe and blue is water left in the pipe).
So then when the the return starts back up the drain has the potential to become whats called air locked due to the air in the lines being trapped between the water in the pipe and the water entering the drains. That air does not want to got down the pipe so this standing water in the pipe creates resistance to the siphons starting by them self until the drain either burps the air back up the drains or is able to break the air up into smaller bits and force it down the pipe and out the sump end. Most drain pipes in this drain setup will completely drain of water during the shutdown to prevent this airlock condition from happening.
It sounds like somehow you have not experienced an airlock yet but I just saw that there was the potential for it to happen in this setup.
A second question I have after thinking this through is in your setup where all three drains go into a single manifold do you experience any noise from air being sucked from your emergency drain into the manifold and then creating bubbles or gurgling at the sump? Because this drain setup is supposed to work based off of siphon it would seam that your emergency drain is a "hole in the side of the straw" and would be introducing air into what is supposed to be a "sealed" siphon.
Sorry about all the questions. Just stuff that popped into my head as I looked at your pictures and read your write up. Thanks for answering and sorry to hear about your daughters leg. I hope she heals up well. Krazie
Edited by Krazie4Acans - 6 hours 33 minutes
ago at 3:27pm