Bean animal drain issue

[DanP-SD]

It’s possible that you were right on the line before — the water level was higher relative to the pipe bottom than ideal but just low enough to let the air out — and then something very minor pushed it over (like opening the gate valve a little, a slight increase in the sump level, etc) was enough to create an issue.

Is the water level fixed in your crash box or does it rise when the return is off and lower once everything is up and running? Most sump designs would be the latter. If so, I’d make sure the pipe is only long enough to protrude an inch or so into the water when the pump is running and the drain is properly working.

If adjusting that fixes the issue, you should make sure the second pipe (the one from the open trickle channel) is the same length so it can easily start a siphon in an emergency.

 

[BeanAnimal]

I don’t think the water level in sump or how much it covers the pipe matters that much,

It matters a lot -- the deeper the the discharge, the harder it is to purge air. The pipe should terminate just below the waterline at normal operating level. A few holes can even be drilled just above the water line to ensure that air purges easily.

@OCJoeR ^^ this is important

but not having a gate valve does. You’ll never have it dialed in with a ball valve, it simply doesn’t allow you to adjust the volume fine enough to keep the siphon steady.

Gate valves can certainly make it easier to adjust, but the original design had ball-valves in it... and you may be shocked to know that ~20 years later, it is still running with ball valves. The siphon valve may need adjustment once a year or two...

Why ball valves? When I built the system that is what I had on hand. The spears gate valves were close to $100 each, even back, and were very hard to source (Aquatic EcoSystems, and plumbing supply houses). Not only were they expensive, they were huge compared to the ball valves, even with added unions.

So the system was setup, and I have never really found a need to swap them out, even though (3) brand new 1.5" spears valves have been sitting on my shelf for over a decade, for that purpose.

You may have gotten lucky for a while initially, but it only takes a slight alteration in flow to throw it out of whack.

Actually - depending on variables like flow, overflow box configuration and plumbing size, the system can be extremely forgiving and dynamically "self tuning" -- that was part of the design criteria.

The original bean animal style overflow has 3 ball valves, one for each stand pipe, which gives you greater flexibility with adjusting flow, but the modern design incorporates a gate valve.

It has three ball valves, because I originally configured each standpipe to have interchangeable functionality, and so that I could isolate any individual intake to dismantle the lower half for maintenance cleaning... which never happens.

The only standpipe that needs an adjustment valve is the siphon standpipe.

 

[OCJoeR]

Here's a photo of the main drain line in the sump. It's about an inch or so below the water level when the system is running.

 

[Ef4life]

Those 90* elbows make your drain a siphon on your beananimal drain. If it breaks the siphon it can’t drain and will overflow. Remove those 90* elbows to allow the water to drain naturally via gravity

But imo it seems to me your bulkheads are quite high up to drain properly

 

[BeanAnimal]

Those 90* elbows make your drain a siphon on your beananimal drain.

Hi - If setup as designed, the 90's do not create a "siphon" in the open channel.

If it breaks the siphon it can’t drain and will overflow.

No - Even as high as the standpipes appear to be set in the photo, they are below the rim (flood level) of the aquarium and will act as drains.

But imo it seems to me your bulkheads are quite high up to drain properly

Possibly too high for the desired operation level of the tank, but this simply means that the water level in the aquarium will be a bit higher and the depth above the weir deeper.


But - hey, what do I know... may be best to consult the original designer if you don't believe me :)

 

[OCJoeR]

Hi Bean,

I did notice in your diagrams you have sanitary Ts coming out of the tank with short pieces of PVC going up with caps and then the drains going down. I just used elbows on mine so there are no sections of PVC going up. Could this be an issue? Also the elbows coming off the bulkheads in the box have slits cut into them, mine don't. Again could this be an issue?

By the way, right now everything went back to running properly.

Joe

 

[BeanAnimal]

Hi Bean,

I did notice in your diagrams you have sanitary Ts coming out of the tank with short pieces of PVC going up with caps and then the drains going down. I just used elbows on mine so there are no sections of PVC going up. Could this be an issue? Also the elbows coming off the bulkheads in the box have slits cut into them, mine don't. Again could this be an issue?

By the way, right now everything went back to running properly.

Joe

Joe, the open channel needs a way to allow air in. At low flow it will not “siphon” because there is not enough water to allow the standpipe to purge the air and form a vacuum… but it will be unpredictable. So yes it needs the tee on the outside or at the very least a hole drilled on the inside elbow with an air intake hose attached.

The slots don’t matter. In my original setup they were to prevent fish from making it to the sump. I ran an ope. Coast-to-coast weir and had some small fish that would make it into the overflow.

 

[OCJoeR]

Is the "open channel" the secondary drain? If so that does have an air line at the top of the elbow. I thought I had a photo of the top but I guess not. Also, someone mentioned using a gate valve rather than a ball valve. I've had the ball valve since I set it up and I don't think that is the problem.

 

[BeanAnimal]

The Valve is not the problem, trapped air in the full siphon pipe likely is. Drill a few holes above the water line to allow it to purge

 

[OCJoeR]

Will do. Thank you.