Internal horizontal overflow 1/24/10
Hi crew, hoping (yet confident) you can help me.
<We'll try>
I have a 150G glass tank, with another 120 or so gallons inline through sump and 56 gallon refugium. My tank is about a year and a half old and, although I am quite pleased with how things have gone, I set things up before I found your site and inevitably now wish I had done some things differently. In case this info is needed, it is a mixed reef tank with (unfortunately) too many fish.
<Good start...>
I recently lost my job so I have a bit of time (and money) on my hands so I though I would change things around a bit to combat an algae problem that I can't seem to kick. Won't bore you with all the details, but I would like you to know that the advice you have given others has helped me tremendously and I am confident that with these changes (to livestock mix and number, circulation, source water and lighting) things will soon look up. Who knows, when I am no longer as distracted by my green tank I may find the motivation to look for another job!
<Wow! Great!>
One of the things I would like to change is the circulation in the tank.
Currently, I rely on a Quiet One 6000 and 4 Koralia powerheads of various strengths to create flow. My most significant change will be the addition of a closed loop manifold powered by a Sequence Barracuda at 4500 g/hr at 0 head, which will draw water from 2 new holes that I will drill in the back wall just below the existing overflows. Additionally, though, I would like to replace my two internal overflow boxes with a long box that spans the length of the back wall and ties in not just the existing 1.5 inch bulkheads but also the 1 inch that is currently used as a return. This will look a little nicer in the tank, give me an addition 300 g/hr flow through capacity, and also improve surface skimming. Do you think this is wise?
<Mmm, so far, yes>
My question relates to this last modification. Can you please refer me to a vendor or site that can make such an overflow?
<Yes... or at least my best choice of where to ask for this outfit. Contact Mike (info@ or call) at Glass-holes.com>
Alternatively, if you know of none or if you think that such an overflow would be too expensive to purchase or ship, can you give me some pointers to build one myself?
<Yes, certainly>
I am fairly handy, but do like to do my research before doing something not tried before. As it is a glass tank would I not have some challenges in attaching and sealing an acrylic overflow?
<Not hard to do... with the tank empty, not (acrylic) bowed from age...>
You guys (and gals) are awesome. If I am lucky enough to have Mr. Fenner himself read or respond to this, I would like to compliment him on a thoroughly entertaining and informative book - Reef Invertebrates - which I have not been able to put down since getting it from Santa this year.
Your knowledge and dedication to the hobby are inspiring, as is the respect you obviously have towards all aquatic life.
Andrew (from unseasonably warm Toronto, Ontario)
<Thank you for your kind, encouraging words. Do chat w/ Mike... and maybe ScottV... and we'll aid your efforts in whatever ways we can/may. Cheers, Bob Fenner>

Internal Horizontal Overflow (and some words of praise for BobF!) -- 01/24/10
Hi crew,
<<Hey Andrew>>
Hoping (yet confident) you can help me.
<<I shall try [grin]>>
I have a 150G glass tank, with another 120 or so gallons inline through sump and 56 gallon refugium.
<<Excellent>>
My tank is about a year and a half old and, although I am quite pleased with how things have gone, I set things up before I found your site and inevitably now wish I had done some things differently.
<<Oh?>>
In case this info is needed, it is a mixed reef tank with (unfortunately) too many fish.
<<Ah'¦>>
I recently lost my job so I have a bit of time (and money) on my hands so I though I would change things around a bit to combat an algae problem that I can't seem to kick. Won't bore you with all the details, but I would like you to know that the advice you have given others has helped me tremendously and I am confident that with these changes (to livestock mix and number, circulation, source water and lighting) things will soon look up.
<<Good to know>>
Who knows, when I am no longer as distracted by my green tank I may find the motivation to look for another job!
<<Ha!>>
One of the things I would like to change is the circulation in the tank. Currently, I rely on a Quiet-One 6000 and 4 Koralia powerheads of various strengths to create flow. My most significant change will be the addition of a closed-loop manifold powered by a Sequence Barracuda at 4500 g/hr at 0 head, which will draw water from 2 new holes that I will drill in the back wall just below the existing overflows.
<<Okay>>
Additionally, though, I would like to replace my two internal overflow boxes with a long box that spans the length of the back wall and ties in not just the existing 1.5 inch bulkheads but also the 1 inch that is currently used as a return. This will look a little nicer in the tank, give me an addition 300 g/hr flow through capacity, and also improve surface skimming. Do you think this is wise?
<<I don't see anything that should be a problem'¦assuming you have the skills/DIY savvy to make the change>>
My question relates to this last modification. Can you please refer me to a vendor or site that can make such an overflow?
<<If you provide the detail/dimensions, most any tank manufacturer should be able to cobble one together for you. You could also contact Glasscages.com and discuss your needs with them as I have seen pictures of tanks they have built with such overflows>>
Alternatively, if you know of none or if you think that such an overflow would be too expensive to purchase or ship, can you give me some pointers to build one myself?
<<Up to you to decide what is 'too expensive,' but construction is essentially a long narrow trough where the tank panel makes up the 'back side' of the trough'¦built deep enough to accommodate the bulkheads'¦and positioned with the upper lip at the desired water height. And by the way'¦'teeth' along the upper edge of the overflow are not necessary. Here's a pic that should make construction pretty much self-explanatory: http://forum.marinedepot.com/Attachment181.aspx >>
I am fairly handy, but do like to do my research before doing something not tried before.
<<Then this project shouldn't be a problem. Do search the Net/hobby forums a bit for discussions and pics'¦there's a number of hobbyists who have utilized this type of overflow>>
As it is a glass tank would I not have some challenges in attaching and sealing an acrylic overflow?
<<Indeed'¦ I very much encourage you to have the overflow made/construct it of the same material as the tank'¦glass in this case, and then attached with silicone>>
You guys (and gals) are awesome.
<<Aw shucks'¦thanks!>>
If I am lucky enough to have Mr. Fenner himself read or respond to this,
<<I'll tag the title, so hopefully he should see this>>
I would like to compliment him on a thoroughly entertaining and informative book - Reef Invertebrates - which I have not been able to put down since getting it from Santa this year. Your knowledge and dedication to the hobby are inspiring, as is the respect you obviously have towards all aquatic life.
Andrew (from unseasonably warm Toronto, Ontario)
<<EricR'¦from wet and chilly South Carolina>>