Bean animal problem

Bars · May 31, 2021

I've got a nice full siphon, small trickle in the secondary drain, dead silent, everything seems fine. Until I shut off the return pump and turn it back on.

I think it's good to know my return chamber is tiny, just a few gallons. If I close the overflow valve, the return pump wil drain its chamber within a few seconds. Made it this small on purpose so my ATO kicks on quicker, but I'm thinking this wasn't the best thing to do. Also probably good to know, is that my overflow is quite big. A little over a foot long, about 5'' wide and 12'' water height. Height difference between main and secondary drain is about 2''.

My problem here is that it takes a long time for water to start going through the standpipes. When it finally does go, the return chamber is empty, so I have to pause the pump and turn it back on a few times. Sometimes that isn't enough and I have to keep adjusting flowrate.

Any ideas what's wrong? I fear it's because of the small return chamber.

WVNed · May 31, 2021

I sounds like your tank has to be overfilled before the drains will restart. Are they air locking?
Does the overflow box overfill and then suddenly start draining down?

Normally when the return pump is off the sump overfills and by the time the return pump has returned that water to the tank it starts draining down and comes back to normal operating levels.

Bars · May 31, 2021

WVNed said:
I sounds like your tank has to be overfilled before the drains will restart. Are they air locking?
Does the overflow box overfill and then suddenly start draining down?

Alright, I think this is a case of me being an idiot. I have essentially been running a herbie overflow for a bit, because my water level in the overflow was too low. That's when I had these problems, couldn't really get a nice full siphon either. I raised the water level yesterday without turning the pump off/on. I just did however, and eventually the water level in the sump corrects itself without problems.

I did notice that both pipes RAPIDLY drain the overflow box twice after I turn on the pump. Both pipes start draining as soon as the water level rises, until it rises slightly above the secondary's drain elbow. They then flush the overflow box. That process gets repeated a second time. After that everything's fine.

So my initial problem was already solved. I don't think the flushing is part of the deal though, is it?

WVNed · May 31, 2021

It wont hurt as long as nothing overflows. The flushing is them purging air.

There is air for example in an empty full siphon drain. The bottom is below the water level and the top gets covered when the pump starts. The air tries to rise in the drain as it fills and stays in the pipe until enough water is above it to push it out the bottom and you get a flush. The drain runs much slower until the air is purged to so you get more water than usual in the overflow box

An open non full siphon drain will flush as well if it gets covered with enough water to flush all the air out of it. It becomes a full siphon drain for a moment.

You may get a couple of cycles of this until the levels all become normal.