Hole placement?

[MizTanks]

Are these ok? The masking tape is just temp :)

Overflow
9308

Return
[9310

[Tom@HaslettMI]

I prefer to have the overflow centered (left to right) on the back of the tank. If you're going to have it on the side be sure there is enough room for the overflow box to fit.

Tom

[tcp316]

I also prefer the center of the back of the tank. I had a corner overflow once and the side of the tank did not look as clean and was more difficult to maintain.

[MizTanks]

I'll have plenty room for a mag cleaner to get between the box & side wall.
I just think that the two should be at opposite ends from one another. Know what I mean? Then I'm not just sending the return water right back down the overflow.

[binford4000]

I vote center too! It appears your return is far enough away. At worst bring the return down lower then the drain.

[AZDesertRat]

I like center too with a split return, one in each corner. I wouldn't lower the return as you will have backsiphonage problems to the sump when power is off, keep it as high as possible since it will determine the tank level in a power outage.

[MizTanks]

Is there any performance reason for the box to be in the center? Or is it strictly a personal preference?
I've actually raised my return a little more. Back siphon reasons. 20g sump, not much room.

[AZDesertRat]

With one return your thoughts on having the overflow at the opposite end is probably best performance wise since it makes the water travel the longest distance across the tank to the oveflow and fewer dead spots. I prefer the dual returns myself so you eliminate even more dead spots, much like having two powerheads or wavemakers and having the flows converge in the front center. With this format the center overflow then makes more sense.
I feel for asthetic reasons the center oveflow makes sense since it is easier to hide or at least less noticable and can be hidden behind rockwork or eventually corals. When it is placed close to a corner it impedes on your view from the side.

[Tom@HaslettMI]

Is there any performance reason for the box to be in the center? Or is it strictly a personal preference?
I've actually raised my return a little more. Back siphon reasons. 20g sump, not much room.

I'm not sure which MP10 setting you're planning to use. If you want a standing wave in your tank then the center overflow is key. The wave created by my wavebox would wreak havoc on an overflow positioned in the corner of the tank.

Tom

[MizTanks]

Wont be doing no wave action-lol. Nutrient export has worked well on my 26g.

I just saw another 40b setup exactly like I'm wanting mine. With the box on the opposite end, it looks really sweet! Entire center of tank is open-nice!

[binford4000]

I like center too with a split return, one in each corner. I wouldn't lower the return as you will have backsiphonage problems to the sump when power is off, keep it as high as possible since it will determine the tank level in a power outage.

All you need to do to stop the siphon is drill a small hole in the return pipe or Loc line in the tank. Not a big deal. Really, you should stick to what you invision your tank should or will be,seams your doubting every step of your build. You've got lots of experience trust yourself you'll enjoy it much more.

[MizTanks]

All you need to do to stop the siphon is drill a small hole in the return pipe or Loc line in the tank. Not a big deal. Really, you should stick to what you invision your tank should or will be,seams your doubting every step of your build. You've got lots of experience trust yourself you'll enjoy it much more.

(((HUGS))) Thanks Chuck!!

[AZDesertRat]

NEVER EVER rely on drilled holes. Just like a check valve they require cleaning and maintenance and will still eventually fail, almost guaranteed.
All it takes is a piece of algae, a snail, a small fish, an anemone, some food etc, to cover the hole and you are done.

The ONLY reliable method of backflow prevention is the simplest form known to man, requires zero maintenance or cleaning and cannot fail ever. An air gap. Leave the return close to the surface so with only a small, very easily calculated backsiphonage until the return is exposed to atmosphere the siphon breaks and the flow stops. no guessing and you can sleep soundly at night. We all know water cannot jump uphill so it cannot fail.

In my case with a 100G display I siphon 3.5 gallons to my 30G sump before the siphon breaks. It is as simple as length x width x the 3/4" or 1" or whatever you are comfortable with divided by 231. Mine is 18" x 60" x 3/4" before the dual returns are exposed and it cannot drop aqny further than that and it cannot fail, simple as can be and no cleaning or sleepless nights wondering if I am going to have a flood when the power goes out.

[MizTanks]

I'm all set! Have seen several exact setups like mine, using the same Gla$$ Holes kit. So I'm good to go. Just gotta barrow a drill-lol.

[MizTanks]

All done! 2 perfect holes! End of this thread as the 40b now has her own :)

[jimsflies]

Well...you can't end it like that Jamie... You need to mention the one bad hole and any advice to others attempting to drill their own tank. :)

[MizTanks]

Well...you can't end it like that Jamie... You need to mention the one bad hole and any advice to others attempting to drill their own tank. :)

Dang I'm all over the place with this build-lol. What happened was that at the end of drilling the first hole the drill stopped abruptly which is what I believed caused it to crack.
I started drilling on #3 (http://www.captivereefs.com/forum/usertag.php?do=list&action=hash&hash=3) as the bit wouldn't rotate on #1 (http://www.captivereefs.com/forum/usertag.php?do=list&action=hash&hash=1) . But I never turned it down like I should I have once the groove was established.
I don't know if I'm explaining this right-lol.