Overflows. Internal or External

[Madreefer]

I started to ask this in Kiens journal but decided I did'nt want to clutter his thread up.
What are people thoughts on external vs internal overflows? My tank is goin to have an internal coast to coast with herby drains, but it's going to be taking away 6" of valuable real estate from my fish and corals. But I dont want to have the tank out any farther than it already will be from the wall. Once setup I wont have access to the back of the tank (the outside)

[kien]

it's going to be taking away 6" of valuable real estate from my fish and corals.

^ this is my take on this.

I had a tank with an internal overflow and I didn't like it for this reason, and for the reason that it made it more difficult to get good flow in that tank. If you can move all your plumbing to one side/end (of the back) of your tank so that it is easy to access the herbie valve you should be OK.

[sphelps]

External is typically the preference however it comes down to the desired layout (how the tank fits in your spot). If the external is too obtrusive then internal is the only option. For internal overflows my preference is a single small center or corner overflow. IMO coast to coast for internal takes up too much space and I'm not a huge believer there is any "real" worth while advantage to it. While the theory of better surface skimming holds true it's kiboshed when you consider the screens typically used and the surface agitation/waves caused by in tank flow.

[AdamsB]

I've been checking out some MACNA coverage since I didn't attend this year (here's hoping for next year) and came across this overflow. I think it's one of the more attractive ones I've ever seen, not sure on its availability though. Posting from my phone so I'm not sure if the link will embed

http://m.youtube.com/watch?v=TtXkntfYgsM&desktop_uri=%2Fwatch%3Fv%3DTtXkntfYgsM

[sphelps]

I've been checking out some MACNA coverage since I didn't attend this year (here's hoping for next year) and came across this overflow. I think it's one of the more attractive ones I've ever seen, not sure on its availability though. Posting from my phone so I'm not sure if the link will embed

http://m.youtube.com/watch?v=TtXkntfYgsM&desktop_uri=%2Fwatch%3Fv%3DTtXkntfYgsM

The only reason I see for this design would be a result from not being able to notch the glass/acrylic. It's just an external overflow without a notch resulting in the need for an additional internal box.

[AdamsB]

The only reason I see for this design would be a result from not being able to notch the glass/acrylic. It's just an external overflow without a notch resulting in the need for an additional internal box.

I agree. However I'd feel comfortable installing this overflow. I have no idea how to etch out glass for an overflow, which may not be hard but then confidence and correct tools are a factor. Also this can be used on rimmed tanks as an aftermarket install, like an undrilled 120 marine land. I'm not sure if they sell publicly or only install on their own tanks. I drilled my 90 for a small overflow box and considering that with a lid was $90 or so I'd rather fork out the extra "little" for this.

[reefwars]

hi bill

i took the liberty of making you a drawing.

in this design i went with a semi coast to coast overflow , by doing so it allows both of your returns to be tee'd off and ran on either side of the overflow box and will be hidden by the acrylic back panel, a slip x threaded bulkhead is then used with loc-line and flow dispurser.

i did it as a bean animal with 2 x 1 1/2" drains and a 2" emergency drain

both returns are 1" and a valve(union BV preferably) on both returns are used to control flow.


this design allows you to access your ball valves from the back of the display without having to reach in your box , it also allows the maximum volume to aqua scape with.

by doing a bean animal you allow yourself a bit less tuning of the herbies gate , but in turn will cost a bit more in plumbing as you are adding an extra drain.

1 is a full syphon, 2 is a trickle or so and the emergency stays dry untill its ever needed(god forbid)


here some jpegs i made i can adjust anything you like if you just tell me what you would like to change and the dimensions you would prefer.

sorry for the delay buddy and hope you dont mind me poisting this public to help with design.

60 x 30 x 36h
19mm all around

http://i1315.photobucket.com/albums/t599/conceptaquariums_denny/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuildoct212013_zps761727ed.jpg (http://s1315.photobucket.com/user/conceptaquariums_denny/media/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuildoct212013_zps761727ed.jpg.ht ml)

http://i1315.photobucket.com/albums/t599/conceptaquariums_denny/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild2oct212013_zpse393bf91.jpg (http://s1315.photobucket.com/user/conceptaquariums_denny/media/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild2oct212013_zpse393bf91.jpg.h tml)

http://i1315.photobucket.com/albums/t599/conceptaquariums_denny/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild3oct212013_zpsac38cd66.jpg (http://s1315.photobucket.com/user/conceptaquariums_denny/media/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild3oct212013_zpsac38cd66.jpg.h tml)

http://i1315.photobucket.com/albums/t599/conceptaquariums_denny/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild6oct212013_zps90780635.jpg (http://s1315.photobucket.com/user/conceptaquariums_denny/media/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild6oct212013_zps90780635.jpg.h tml)

http://i1315.photobucket.com/albums/t599/conceptaquariums_denny/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild4oct212013_zpsfd56c354.jpg (http://s1315.photobucket.com/user/conceptaquariums_denny/media/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild4oct212013_zpsfd56c354.jpg.h tml)

http://i1315.photobucket.com/albums/t599/conceptaquariums_denny/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild5oct212013_zps919b13c7.jpg (http://s1315.photobucket.com/user/conceptaquariums_denny/media/new%20concept%20aquariums%20build/tank%20drawings/madreeferbilltankbuild5oct212013_zps919b13c7.jpg.h tml)

:P

[kien]

THIRTY SIX INCHES TALL??!! ZOMG are you a giant ?!

[sphelps]

I'd be more concerned about the 2" bulkhead in a 5" overflow, minus the glass that's probably 4.5", OD of bulkhead = 3.875 so clearance on each side is only 5/16" provided it's perfectly centered and not including the clearance needed for the silicone bead. Not something I would attempt but then again those concept guys are crazy in a good way :thumb:

[kien]

..those concept guys are crazy in a good way :thumb:

:lol:

[reefwars]

I'd be more concerned about the 2" bulkhead in a 5" overflow, minus the glass that's probably 4.5", OD of bulkhead = 3.875 so clearance on each side is only 5/16" provided it's perfectly centered and not including the clearance needed for the silicone bead. Not something I would attempt but then again those concept guys are crazy in a good way :thumb:

smart man lol should read 6" not 5:P

[Madreefer]

Thanks for all the suggestions. Denny I will respond on my build thread

[zum14]

Personal preference is external. I like the bean animal but there's a science to the depth of the overflow box and the piping size and where you run the plumbing. My one attempt was a full coast to coast external. It was about 5" deep but didnt run a ton of flow through it. I was able to tune it so the water ran about 1" below the box height. This resulted in a quiet overflow. My current overflow is a 12" deep internal box and the water is running about 2" below the box height. The way I got this tank I had to run the plumbing at the top of the tank and elbow it down to the bottom of the box so unfortunately the water hits the piping and makes quite a bit of noise. It's 1-1/2" plumbing and running about 3000gph. The issue is if you close the gate valve a bit to raise the water height so its quieter it starts running more water down the balance pipe and that makes more noise. Its not just drill and go.

[Madreefer]

Well after a discussion with my wife I have to settle with an internal overflow. I don't get anymore space in the house for my tank.:sad:
It's her house to and she wins this one. It would push my tank out a further 11". I have alot of confidence in Dave and Denny at Concepts and Paul from OC and i'm sure the pros wont stear me wrong.

[lastlight]

My external overflow on my 400g was no more than 6" out from the tank and I had 1.5" bulkheads inside it. I didn't read the entire thread but 11" seems excessive no?

My current overflow is internal. The box is only about 4" in length from the back of the tank and it only goes down about 8" I believe so doesn't affect where fish swim too bad. Then my pipes exit the back of the tank and 90 down so you have a thin box in the tank and the tank only stick out from the wall the depth of a 90 fitting.

[Madreefer]

I didn't read the entire thread but 11" seems excessive no?

.

I should have explained better. My tank right now is 29" wide and 5 1/2" away from the wall. If I went with the 6" external overflow which would be ideal, my tank would stick out 6" more so a total of 11" from the wall.

[kien]

I should have explained better. My tank right now is 29" wide and 5 1/2" away from the wall. If I went with the 6" external overflow which would be ideal, my tank would stick out 6" more so a total of 11" from the wall.

That sounds to me like you are wanting your overflow box itself to be 5 inches away from the wall. That seems excessive. Does your overflow box need to be that far away from the wall? All your plumbing runs down from your overflow box, not out the back of your overflow box doesn't it?

[kien]

also, why is your overflow box so wide? Is there a specific reason for such a wide overflow box? There seems like a lot of space in there to collect detritus. If you plan to cover your overflow with grates I would imagine that much overflow is going to be noisy. Imagine dozens of tiny waterfalls splashing into your overflow box. If you don't plan to cover it, imagine fishing out fish from your overflow box often :lol: Anyway, it seems to me like you could easily get away with an overflow 1/3 that size.

[Madreefer]

That sounds to me like you are wanting your overflow box itself to be 5 inches away from the wall. That seems excessive. Does your overflow box need to be that far away from the wall? All your plumbing runs down from your overflow box, not out the back of your overflow box doesn't it?

Well the new tank won't have to be as my Vortechs will not be on the back of the new tank which they are now. With the curved glass they can't be put on the side. But there is a power outlet right in the middle of that space. I can barely reach it now and this tank is only 57" long. But you just now got me thinking about getting a large enough hole to be made by the cabinet makers so I can access it through the back of the stand. Thanks. So 2" from the wall should be good enough? It would actually be better, than I wouldn't have to move my hanger for lights. They're lighting up my overflow now.

[Madreefer]

I'm just listening to the tank builders. I'd prefer it to be not as wide for more tank space. I think it has to do with bulkheads. I'm also getting pieces of glass or acrylic attached to the back wall to act as a shelf to place a black acrylic cover over the overflow.

[kien]

.. getting a large enough hole to be made by the cabinet makers so I can access it through the back of the stand.

This is a good idea. I too have an outlet right at the back of my tank and ran an extension cord through my stand and mounted a powerbar underneath my stand to plug everything into.

[reefwars]

I'm just listening to the tank builders. I'd prefer it to be not as wide for more tank space. I think it has to do with bulkheads. I'm also getting pieces of glass or acrylic attached to the back wall to act as a shelf to place a black acrylic cover over the overflow.

if we go with a 2" bulkhead for the emergency then the overflow box width will be 6" from the back of the tank , so if your tank is 30" the overall width is now 36" , as far as spacing goes from the wall as long as your tank is level then 1/2" -1" is more than enough, you need only enough space so that the box doesnt touch when the tank settles.

if we go with 1 1/2" drains then the box can be 5" and 4" for a 1" or 3/4" bulkhead.

we dont do smaller than 4" as it becomes impossible to work in.


hth

will have those diagrams shortly for you buddy:)

cheers

denny