bean animal overflow system

[jon1985]

I want to use a bean animal overflow system on my 180 gallon tank but dont want to use a coast to coast overflow box.  Will the system still work with an overflow box in the middle of the tank right to the bottom?

In all the  info I can find about the bean system the drains are very close to the bottom of the overflow box.  Obviously this wouldnt work  with a full height overflow box.

Any one using this overflow setup?

ideas?

[fischkopp]

I installed a bean style overflow without coast to coast in my 180 and switched it one for the first time this weekend! 

I use an overflow box in the corner, it contains the full siphon and the overflow drain. Both are simple elbows, the full siphon facing down, the excess overflow facing up. The opposite corner has an elbow as for emergency overflow as well as the return. One thing I noticed is that you want to have the excess overflow going almost to the top of the overflow box, so that the water level inside the overflow box is only slightly lower than in the tank to eliminate noise from water entering the overflow box.

The full siphon is submersed in overflow box and sump. If you add a little hole below the water level in the sump, the full siphon will start automatically when you power on your pump; all the air in the return plumbing gets an easy exit path that way.

All in all it work like a charm. No noise whatsoever.

[jon1985]

so you have the syphone elbow just below the edge of the oveflow box? Is it adjustable at all?

I have no problem with corner overflows, Im not really set on the center box, just figured it was easier to make 1 instead of 2 boxes.

[fischkopp]

No, the full siphon is close to the bottom. You will need valve in the full siphon return path in order to control the amount that is returned. It is set so that it returns the bulk of the water, but not enough to drain the overflow box empty. Equilibrium is hard to find, so set the valve so that the water in the overflow is slowly rising; the excess elbow will return it to the sump.

The main reason I use a corner box is that I didn't want a visual distraction in the center of the tank. It also works well circulating the water from left to right. I am using it for freshwater, so your considerations may be different.

[jon1985]

so the syphone tube is close to the bottom of the tank?  I assume the excess overflow is near the surface?

I dont understand where  you drill the hole in the syphone tube if it is close to the bottom. 

I think the whole purpose is the same wether talking freshwater or saltwater, get water out of the dt into the sump and filters then back into the dt as silently as possible.

[lost_at_sea]

I believe the hole in the siphon drain goes just under the operating waterline in the sump.

The Siphon elbow just needs to be facing down, the emergency elbow facing up BUT MUST be below the physical top of your tank.  (It's whole purpose is to catch water if it rises before it flows over your tank)

Keep in mind if you run this system you'll need to make sure you have a return pump strong enough to maintain the flow required for a siphon.  Overkill the return pump (a bit) and then throttle it back with a valve to get the flow just right.

If the return pump is too strong (or the siphon drain gets clogged) the water in your overflow will rise, eventually to be caught by your emergency drain.  If the return pump is too weak the water in the overflow box will go down causing your siphon drain to switch in and out of siphon and sound a lot like a toilet.

[jon1985]

well I currently have a pump rated for 1650gph but not sure how much it decreases with the head height.  I will start with it as I have it and buy a bigger one if need be.

[fischkopp]

so the syphone tube is close to the bottom of the tank? 

no, bottom of the overflow box. I should mention that the tank is drilled in the back top corners, the overflow box sits in the back top corner and is only a couple of inches deep.

I assume the excess overflow is near the surface?

yes, near surface inside the overflow box. the emergency is a little above the surface in the tank.

I dont understand where  you drill the hole in the syphone tube if it is close to the bottom. 

since the full siphon is submersed in the overflow, the water pressure can push out the air when it is first starting to siphon. But usually the sump is submersed as well, so water in the sump will push against it, so air is trapped. A little hole just below the water level in the sump will eliminate that pressure, allowing the air to escape.

[jon1985]

oh I see now.  When you said corner overflow I thought it went to the bottom of the tank as I have never seen a corner overflow that doesnt.