Pro and cons of different styles of over flows
 

I need to drill additional holes in my 270g for drains as much as I don't like drilling glass but that's for another thread. I plan to drill the back but a long time reefer friend says I should drill the bottem for strength reasons. So I ask you guys what do you think would be the way to go.

Beananimal
 

I did a beananimal on my system. It's completely silent and I have peace of mind that the likelihood of a failure would be minimal.

just a couple of tips. The end of your drain in your sump should only be about two inches below the water level. Try to limit any horizontal runs. A gate valve will work better than a ball valve.

Really, I can't see why drilling the back is any different that drilling the bottom. I wouldn't say that drilling the back is any weaker. The only difference between the two positions is that the holes on the bottom have even hydraulic pressure on them, where on the back panel a hole has a slight pressure differential from the top of the hole to the bottom of the hole. Drill holes which ever way makes the most sense for your overflow design. For internal overflow weirs, it makes sense to just drill in the bottom and run the stand pipe straight down. If you're doing a coast to coast, beananimal, external overflow, etc where the water needs to go out the back, well then drill it as such.

My Beananimal
http://www.canreef.com/vbulletin/sho...d=91225&page=2

Whatever internal to the overflow will likely be just a simple one. The box it's self will be an almost coast to coast internal so by going out the back I loose very little internal space. So would that be the best way or should I do it that the overflow is shaped like a "T" so the water would flow to the center and then go into the return plumbing.

Drilling through the back can lead to a stress crack if the weight of the plumbing hangs off the bulkhead. Had it happen to me on a 46 bowfront once. Not pretty. If you do go through the back make sure you support the piping with blocks and hangers so there's no load on the bulkhead.

Turned my 220g into a salt tank with 2 internal overflow boxes, each one is 24" long x 6"x 6" and I have them up in the corners. I drilled 3" holes for each box for the bulk heads and 2" pipe goes down to the sump. Over flows work great. If I had my choice I would have external overflows to give the tank a real clean look.

I drilled 2 holes in the back at the top of my 90 g and used an internal 1200 gph overflow.
Bought it from BRS 12"x6"x6" and installed it as per their instruction video, going do the 1" herbie drain with a redundent emergency 1" drain. Return from the sump will be back into the tank over the rim.

i will take the advice of the supports for the plumbing I've opted for 2 of the brs 2400gph overflows in addition to the existing over flow. the brs ones will have a 11/2" "t" oriented vertically with a cap on the upper end with a hole drilled in it similar to a durso stand pipe which i have on the 175g and is dead silent. the existing over flow will be a 2" durso more-so meant as a emergency drain. not exactly looking forward to drilling the holes but gotta do what you gotta do.

How much flow are you trying get out of that sucker? If you put all that though your sump you gonna have raging waterfalls in there! Lol. Is the new overflows to feed a closed loop? If so you don't need an overflow, just a submerged bulkhead with a strainer to keep critters out.