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]

Originally Posted by Madreefer

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=TtXkntf...%3DTtXkntfYgsM

[sphelps]

Originally Posted by 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=TtXkntf...%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]

Originally Posted by sphelps

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]

Originally Posted by 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

: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

[kien]

Originally Posted by sphelps

..those concept guys are crazy in a good way