Dual overflow plumbing

EDJFA

New member
I'm just days away from (hopefully) seeing water in my new tank. It's a 210g with dual overflows. I'm setting it up in my office where I meet with clients and talk on the phone all day long. So, my system needs to be really quiet.

Each of the overflow boxes has two holes drilled in the bottom of the tank. I've been reading about the Bean Animal system and if I could pull that off it would be perfect. But that system uses three standpipes in the same overflow box. I have thought about putting the the third emergency drain in the second overflow and using the fourth hole for the return from my sump.

This would basically mean that I've got one functioning overflow. The threads I've read have made it sound like you can run as much flow as you want through the one main drain. Only in an emergency would that second overflow drain be used. It would mean that the first two pipes have become clogged somehow rendering the first overflow useless.

I'm not trying to create any massive water movement in my display with the return. Just trying to get the water down to the sump for skimming/heating/dosing, etc and then back up again.

Am I wrong in my assumptions with the overflow setup?

If anyone has any other suggestions, I'm open to hearing them.
 

Kdawg_69

New member
just do a herbie its easier n almost as safe if u do it right with some gate valves


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SGT_York

New member
That will create problems.

The trick is balancing the water in the overflows. If you use one overflow for a siphon and open channel all of your water will flow to that one overflow leaving the other emergency, return stagnant. So you can fill it with sand and live with the issues or reconfigure the drains.

If you use siphon dry emergency in one return and open channel in the other there are issues with the overflows both trying to run 50% of the water capicity the issue with this option is that the open channel if not set PERFECTLY will not be managed by the siphon and will generally try to suck in way too much water or raise the water in the display creating all sorts of additional problems. Essentially you have one herbie and one durso if you go this route and the durso won't be quiet. You want the water level to be set by your overflow walls not the durso which means you need the open channel with the siphon line.

I have tried three different methods and realized the BA just doesn't work with dual reef ready overflows. You can drill an additional hole in each and it will work fine. You can go with two herbies which works fine but you need to run your return over your tank unless you drill another hole. I joined both herbies into one gate valve but there are plumbing difficulties you need to research before going that route.

There is another method where someone altered the overflows placing a 1" pipe connecting the two near the bottom hidden. Theory sounds good but I've never tried it as it's just too much risk/work.

If you can drill the additional holes in the side. If not go with the two herbies and ensure you have a good method to keep algae/snails out of the siphon lines.

Congrats on the tank 210's are great dimensions.
 

uncleof6

New member
I'm just days away from (hopefully) seeing water in my new tank. It's a 210g with dual overflows. I'm setting it up in my office where I meet with clients and talk on the phone all day long. So, my system needs to be really quiet.

Each of the overflow boxes has two holes drilled in the bottom of the tank. I've been reading about the Bean Animal system and if I could pull that off it would be perfect. But that system uses three standpipes in the same overflow box. I have thought about putting the the third emergency drain in the second overflow and using the fourth hole for the return from my sump.

This would basically mean that I've got one functioning overflow. The threads I've read have made it sound like you can run as much flow as you want through the one main drain. Only in an emergency would that second overflow drain be used. It would mean that the first two pipes have become clogged somehow rendering the first overflow useless.

I'm not trying to create any massive water movement in my display with the return. Just trying to get the water down to the sump for skimming/heating/dosing, etc and then back up again.

Am I wrong in my assumptions with the overflow setup?

If anyone has any other suggestions, I'm open to hearing them.

No, you are not wrong. As of yet, I have heard of one "confirmed" use of a bean system in dual overflows, and it was done backwards—it was not working.

Honestly, I don't think dual overflows is the place for a bean system, or a hacked in herbie either; I may be wrong as I was using siphon systems before herbie published. The best bet is don't buy reef ready tanks anymore, (overflows and holes are usually too small) or pull the overflows and start from scratch.
 

ca1ore

Grizzled & Cynical
I just set up a dual overflow 265 and did a 'sort of' bean animal ..... I have put a Herbie in one and a regular durso and return in the other. Herbie corner is completely silent, durso corner makes slight noise, but relatively low flow thru pipe is ok.
 

uncleof6

New member
I just set up a dual overflow 265 and did a 'sort of' bean animal ..... I have put a Herbie in one and a regular durso and return in the other. Herbie corner is completely silent, durso corner makes slight noise, but relatively low flow thru pipe is ok.

Well if you really examine what is going on, you will see why it makes little sense.

Bascially, given the tank is level, or close enough, flow rate into both overflows will be roughly equal. Therefore, for the system to be anywhere near stable the flow rate needs to be set to the lowest common denominator, which in this case is the durso.

Everyone knows that dursos are not performers, or they should know anyway—otherwise folks would not be hacking stuff together to get away from them in dual overflow tanks. There is no interaction between the durso and the siphon, unless water level is above both overflows making it all one body of water; so you cannot jump the flow rate close to the capactiy of the siphon, or the durso will go nuts. Basically, it is a waste of time, and you would accomplish the same thing with dual dursos.

So have to figure (if the durso is 1.5" all the way down) a flow rate above 700 gph (combined,) but not much above or your durso would be doing more than 'making a little noise.' If you run this tank where it should be run, ~2600 gph, you will have nothing but a mess on your hands.

The "BA" system fits a very strict definition, not in the 'sort of' category. It is already hard enough to keep it clear and concise. It is these loose definitions that are causing the confusion, and giving us unsafe systems like the herbie with a trickle in the dry emergency. Many have talked about it, but I know of none that have done it the right way, in dual overflows, without bridging the overlfows, and I am not certain any have actually done that. Best solution for big tanks like this, is to ditch the overflows and start over.
 

ca1ore

Grizzled & Cynical
I don't think a true BA can be done across dual overflows - at least, I couldn't figure out how to do it! In my case, I don't see any good reason to run anywhere close to 2600 gph through my sump - my guess is I'm less then half of that, probably 1000 or so. So, half runs through the durso into an ATS (so water-air mixture is actually preferred); the other half through the siphon quietly into the skimmer section of the sump. Should either the durso or the siphon become fully plugged, the emergency will manage the load. should both become fully plugged ...... well, hopefully that won't happen.

I think, in retrospect, I ought to have bought a non reef ready version of the tank and installed my own C2C overflow with external BA - too late now though.
 

EDJFA

New member
I'm in the too late now camp with ca1ore. Need to work with what I've got.

Is it possible, maybe advisable would be a better term, to add a third and maybe fourth hole in each overflow to set up a dual BA system with the fourth hole being for the return? Quick measurements (eyeballing really) tell me that the current holes are 1.5". There's a bit over 3" between them. If I drill two more holes, one 1.5" for the emergency drain and a smaller one for the return, would that ruin the integrity of the bottom of the tank in those areas?
 

ca1ore

Grizzled & Cynical
I'm in the too late now camp with ca1ore. Need to work with what I've got.

Is it possible, maybe advisable would be a better term, to add a third and maybe fourth hole in each overflow to set up a dual BA system with the fourth hole being for the return? Quick measurements (eyeballing really) tell me that the current holes are 1.5". There's a bit over 3" between them. If I drill two more holes, one 1.5" for the emergency drain and a smaller one for the return, would that ruin the integrity of the bottom of the tank in those areas?

First and foremost you have to find out if the bottom is tempered or not. Some tanks are; but many are not. Not sure if your tank is a Marineland or not? Mine is and the corner overflows are tight with just the two holes, not sure you'd be able to fit in a third. The other thing to consider is that both corners must be active on some level to prevent stagnant water.
 

woodnaquanut

Premium Member
Extra holes seems unsafe! You need 1.5x the diameter of the hole between the holes.

Are the holes actually 1.5"? That uses a bulkhead for 3/4" pipe (ABS BH) or 1/2" pipe (Sch80 BH).
 

uncleof6

New member
I don't think a true BA can be done across dual overflows - at least, I couldn't figure out how to do it! In my case, I don't see any good reason to run anywhere close to 2600 gph through my sump - my guess is I'm less then half of that, probably 1000 or so. So, half runs through the durso into an ATS (so water-air mixture is actually preferred); the other half through the siphon quietly into the skimmer section of the sump. Should either the durso or the siphon become fully plugged, the emergency will manage the load. should both become fully plugged ...... well, hopefully that won't happen.

I think, in retrospect, I ought to have bought a non reef ready version of the tank and installed my own C2C overflow with external BA - too late now though.

Of course it can be done. Where the dry emergency is, is rather irrelevant, but get the siphon and the open channel in the same body of water e.g. the same overflow, and it will function as the BA is designed to. Where folks get tripped is shutting down one overflow. There is some merit to that line of thought, as rr tanks are already lacking in overflow length sorely lacking, but shutting down one overflow in and of itself is not an issue. Fill it with sand, keep water flowing over it (oopss gotta use powerhead, closed loop won't and doesn't get it done) instant mini dsb. It may not do much, but certainly will not hurt anything, unless it fills up with crud, which it won't if you keep water moving over it.
 

NanoReefWanabe

New member
can you not cut a notch in the top of each overflow and connect them with a trough....essentially giving you a coast to coast overflow...then you can easily do a bean as both of the reef ready overflows will be linked and functioning as one box
 

SGT_York

New member
Yes you can combine the overflows or, "bridge" like uncle stated, into one but the process of adding a round pipe or trough to a curve is difficult and unless done at the bottom can be an eyesore. Diameter of the connecting pipe needs to be significant as well. You can get creative and come up with a good rectangular trough that would look acceptable, but if you are that good with handyskills just redo the overflows, as the reef ready overflows are crap.

Ca1ore, I bet your water level in the durso is fairly even with the water in the display tank??? You can't be pushing 50% of your water return through a durso that is remotely quite but if it is just a bit of water all is well. If it works for you than great, have you tried blocking off the siphon to see what happens? 10X turnover in a sump is on the high side, especially with the new DC powerheads.

Drilling a new siphon line in the back of the tank is probably the best bet for a reef ready tank using the existing holes for emergency/open channels, but based on the OP's comment about a 4th hole you're probably not considering that.

Two separate herbies work fairly well slight balancing and sustainment issues, using the dry emergency with a slight trickle solves those issues with risk, thousands of herbie's work just fine. A joint herbie works if done right, do significant research before starting that approach or you will have issues.

The most important thing to do is ensure that snails and algae stay out of the overflows. I highly recomment placing a lid over each overflow that will keep the light and snails out. (mine has a few holes in the back just in case water goes over the overflow due to teeth cloggs. I tried the strainer approach but it would need to be maintaned as algae would restrict the flow too often for my likes.
 
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fltekdiver

New member
In my 120 with dual overflows I had the 2-1" lines running siphon running into a 1.5" TEE, and below that I had a 1.5" gate valve . I had a heck of a time all the time balancing the two weirs, because my plumbing underneath wasn't equal

On my 180 , I just plumbed it with the 1.5" return line over the back, and the
2-1" siphon lines in each weir are independent , each with its own gate valve

Been working perfect ! I'm very happy I went this way, just worked great

My other drains lines in each weir, and DRY emergency only
 

ca1ore

Grizzled & Cynical
Ca1ore, I bet your water level in the durso is fairly even with the water in the display tank??? You can't be pushing 50% of your water return through a durso that is remotely quite but if it is just a bit of water all is well. If it works for you than great, have you tried blocking off the siphon to see what happens? 10X turnover in a sump is on the high side, especially with the new DC powerheads.

Sorry to say you'd lose that bet :). Water level in the Durso side IS higher than in in the siphon side, but not by much. I'm running a PanWorld 150PS from my basement sump, so probably only in the range of 800 or so gph when accounting for head and friction loss. If you figure both overflows are handling half, then 400 gph down the durso, less if you figure they're not equal. Either way durso is not noisy at all (no fluctuating levels) and the flow through that overflow is sufficient to keep the water moving behind the weir. Siphon, of course, is completely silent.
 

EddieJ

Premium Member
I have the dual Herbie setup in my 210 RR. It's been running for 2yrs+ now. I do not have my siphons tied together as I have a gate valve on each. My sump is in the basement. System works very well for the most part, different Vortech powerhead modes will create some imbalance in the system from time to time. The dry emergencies do have a trickle to them at times, so I am exposed to a very small risk of failure of some sort. I do have these on my overflows

ofcover.jpg


which definitely mitigate the risk of the siphons becoming blocked. I push about 1000 GPH from the basement, which is what I want to flow through my sump. It may not be 100 percent fail safe, but I am pretty sure there is a greater chance of a seam busting or some kind of other failure then my overflow system "overflowing" the tank.
 

SGT_York

New member
Nice lid, makes mine look like junk!

Ca1ore, glad to hear you are happy with the setup, 400G through a straight drop isn't bad, PanWorld pumps are comparitivley noisy, I run the same pump in my 120 but only 5' of headloss so a Durso just won't cut it. What do you use for tank circulation?
 
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