I have a tank building for me. I have yet decided what route should I go with. HOB overflow? or should I have hole (1 hole?) drilled on the bottom behind the overflow? to the sump underneath the tank.. I am looking something like ELOS Mini tank....

tahnks

In my opinion, an overflow and drain pipe is superior to an HOB overflow. It is also common to drill a hole for the return as well. Plus if you decide on a Herbie style drain, that would require two drain pipes.

Since I m having the tank build, I want them to drill them holes too lol...on the corner overflow, should I have 1 or 2 holes drilled to sump( 2 holes in case 1 of them are clogged?) and 1 return on the back wall? What size of holes should I get? 1/4" for that size of tank?

thanks

if this is for the NC12- I would go with 1/2" return line at the very least. I went with 1/2 inch bulkhead fitting on mine- which means you have to drill larger to a 1 1/8" to get the bulkhead fitting in. after I installed the bulkhead fitting- I then installed 1/2"x 1/4" lockline splitter- giving me more options on direction of flow into tank- although, I would assume that this would be located on back of tank-

I'm not sure how big of a tank/sump you are planning. But yeah, I'd use 1" bulkheads for the drains and either 3/4" or 1/2" bulkheads for the returns (depending on the return pump you are planning). Redundant drains are more common in larger systems, but redundancy is never a bad idea if you can spare space they take up.

Actually it's not NC12.
I have the tank custom built. The foot print will be 17"X17"X16" (H), similar footprint like ELOS Mini. It's a 20g tank.

I am thinking about using a standard 10g sump?

So general census, will be like

(2) 1/2" drain hole at the bottom of the tank on the overflow side. 1 hole is good too?
(1) 1/2" return line on the back panel. - drilled 1 1/8" hole to fit 1/2" bulkhead? I have a 1/2" Y loc-line split somewhere Also how high is the return should be? 2" from the top?
10g sump tank with skimmer running + fuge.

What kind of pump is out in the market that is dependable and fairly cheap? Mag 10? what sort of pump should I use for the 1/2" return?

Make sense with the sketch below? I am thinking about 2 drilled holes 1/2" each with 1 return and 1 drain as sketch below.

A 1/2" drain(s) will NOT do; you will need a 1" drain bulkhead(s) at a minimum. The tank manufacturer should know how much larger the hole needs to be to fit a 1" bulkhead.

Remember that the water will drain back down the return line (into the sump) whenever power is cut/lost to the return pump. Therefore you want the return as high as you can to prevent your sump from overflowing when the return pump stops.

Mag 10?

A 9" linear overflow with a one inch drain will handle a maximum of 600gph (plan on less). A Mag 5 would be about all that it could handle. Remember to take into account head height/pressure when determining the flow rate.

You will need to supplement flow with one or more powerheads to achieve enough flow in your display.

oh...so 1" drain and return? Yes I am planning to have maybe 2 K1 or K2 in tank.

A 1" drain and a 1/2" (or even 3/4") return should work fine for your application.

thanks for the number. I have decided to use 1/2" return with 1" drain on a overflow sort of like ELOS build. How about the fuge/sump build? Should I build like 3 sections?

Check out some of these 10g DIY sumps.

Bulkhead Gallons per hour
1/2" -150gph
3/4" -350gph
1" - 600gph
1.5" - 1300gph
2" - 2500 gph

Considering the size of the tank, and the fact that most people do not run more than 10x the diplay volume through their sumps, you could easily get away with a 3/4" bulkhead. Depending on the head hight, you could use either a mag 2 or 3.

this would be more accurate
http://www.grow.arizona.edu/Grow--GrowReso...?ResourceId=188

read the overflow thread for more info
http://www.nano-reef.com/forums/index.php?showtopic=69372

even if your having someone else do the biuld its important to understand the way & why it works your self.
seabass had a great idea in recomending a herbie style drain.

OK a BIG MISTAKE was make during drilling the hole and placing the cover back wall...:partly my part after i talk to the person and i forgotten to change the diameter on the drawing....

So now I have 2 1/5" holes with bulkheads on it. There is not enough room for a 1" bulkhead...

what should I do now? Should I let both holes to be draining and have a return on one of the wall..

HELP

Are the holes close enough to make (router or drill) one 2 3/8" hole where the two holes are? This would fit a single 1 1/2" bulkhead for the drain. You can then drill a hole in the back (if there isn't enough room behind the overflow) for the return. Your other option is to cut out the holes and and make a patch with a more proper hole size in it. This can be be placed on top of the cutout to give you a proper drain. Hope that helps.

Are they actually 1/5" holes or holes drilled for 1/2" bulkheads? If they are for 1/2" bulkheads, you might be able to get away with using them both as drains and drilling another (in the back) for a return; however, that still won't give you a lot of flow.

Yes they are drill to fit 2 1/2" bulkheads.

I am planning to have maybe 2 Koralia hydro 1 or 2 in the tank. Does this help the flow?


here is the hole...i can fit both bulkheads in. Also, should I join both holes in a T to make a single drain into sump?

My overflow.

Takes up no tank area / is silent / water level is easily adjustable by just rotating the 90 elbows.
Cover the drains with "glass mat" or "bar mat"

Used this on three of my own tanks and a few of my reefin buddies have adopted this setup as well.

It helps the display flow but not the flow to the sump. However, the two 1/2" drains will still work with a small return pump like a Maxi-Jet.

I wouldn't, I'd just run both into the sump (keeping them redundant)

You could still do a patch if you wanted:

thanks for all your help. I spoke with the builder, he will help me fix my mistake lol..he said he can replace the bottom piece fairly quick...+A to him!

Because all of the water is always taken from the top of the tank, the placement of the hole in the tank has little consequence on the amount of water that each bulkhead can flow. I stand by my numbers.


/thread hijack