250g Tank Design (In-Wall)

[Jon]

Help, I'm in the final design of my new 250g (96x24x25) tank and need to finalize some hole placement and overflow design questions I have.

First What I know:
- Want to keep mainly SPS and fish
- Want to maximize overflow area to get the thinest possible top layer of organics to feed to skimmer and sump.
- Prefer to have smooth overflow top with egg crate mounted inside box, agian to maximize area and/or slots getting clogged.
- Want average flow through overflow
- Want maximum flow through separate closed loop


Questions:
1) What type of overflow design should I use
2) Where should I locate CL feeds and returns to prevent deadspots
3) What kind of flow rates are recommended for OF and CL

Here are 3 designs I'm working on:

Two overflows about 8" in from each side. 8dx6w
Total linear overflow lenght: 44" (2x 8+6+8)

One overflow located in the middle of the tank. 8dx30w
Total linear overflow lenght: 46" (1x 8+30+8)

One overflow located in the middle of the tank (Calfo Style). 8dx30wx6h
Total linear overflow lenght: 46" (1x 8+30+8)

My only concern with the calfo one is the drain pipe design and gurgling. I can easily control water height in the box with the other by making the pipe different vertical lenghts, but with Calfo the hole is drilled and perminant.

However with any of them what kind of thinness of water can I expect with that lenght of overflow and at the rates suggested?

Thanks in advance for the help,

Jon............

 

[billpa]

Hey Jon

Congrats on the soon-to-be upgrade! A few thoughts:

Why not go with a full length overflow but have the actual box on the outside? That way you could have the benefit of surface skimming the whole tank and be able to have your overflow box. Plus you would not have any eye sores

Good idea using a CL for the majority of your CL. I would definitely look into OceansMotions 4 way (have one and like it alot), or possible using eductors or penductors on a big pump OR possibly those new Vortech pumps that IceCap is distributing. They wouldnt take up a whole lot of space, your tank is in-wall so nobody has to look at the motor end on the outside of the tank, and you feel good knowing that PECO isnt ripping you off

If you are planning on fish and SPS, I would look into a good needlewheel skimmer and feeding it directly from one of your standpipes. That way you are skimming concentrating sludge. Then have the other standpipe go to your fuge.

I think thats all the advice I have right now. Good Luck!

Bill

 

[Sonia Taro]

Jon,

I can not remember but are you going with a BB? I would place the feeds for the Cl in the bottom center of the tank.

As for returns:
2 in the back 3/4 of the way up. 2" BH
2 in each side (one high and one low) 1.5" BH
2 dropping down from the center with OM 1" 360 deg. revolutions.

You would have to use an 8 way but it would be well worth it. Give Paul at OM a call. I am sure you guys can have a very technical conversation. If you do, please send my regards.

My tank is very much like yours and I run a Reeflo Hammerhead for the CL (5520gph) and a Reeflo barracuda (3700 gph) for the system. With the Barracuda you could place some eductors on the returns and knock the socks off the fish. I would do four returns.

I there any option to place your skimmer box on the back of the tank. I love that type of design. I think that you have enough room to do this.

I can not waite to help you put this thing in place and plumb it up.

WDH

 

[Jon]

Hey thanks for the feedback. One thing I forgot to mention is that behind the tank I only have about 14". That's just barely enough to walk behind and service. So I wanted to avoid placing a external box back there as nice as they are. I also only have about 4" from the right side of the tank to the wall. However, on the left I've got a good 3 feet open space. So ideally all the plumbing would come out only the left side, but I think putting a box there might not look the best. An option I was considering if I did put the overflow inside left would be just sheetrock over part of that side to hide it since its mounting in a wall.

As for an external box on the left side, I don't think I would really maximize my overflow lenght since it is only 24" deep. All the other designs give me about 46". So the water skim would be twice as thick.

All this assumes that I think 46" is the right number. From reading about direct observations from others and imperically deriving a few things from the flow calc here on RC. I think with a flow of about 3000gph it will yield a water height of less then 1/8".

Thanks for the help,
Jon.........

 

[Fliger]

Look up "skeets" and check out his overflow. It is a very cool design and might confuse you more. ;-)

 

[dsheel1]

Have you thought about corner overflows?

 

[Jon]

Thanks Fliger, I looked up skeets, interesting design for the overflow and its got me thinking, however a few too many holes in the back of the tank for me.

As for corner overflows, nothing really against them only that you loose a lot of possible overflow area for the same footprint, and in my case since my boxes are 8" deep, that 16" total lenght or about 35% of the original 46". So I'm just trying avoid if possible.

Thanks,

Jon.........

 

[Jon]

Hey all,

Just some followup to this thread. I've taken the suggestions and came up with what I hope is the final design, so comments please.

The tank is still 96" x 24" x 25". The (2) overflows are 8"x8" square with (1) 2" bulkhead in each. The CL returns are noted on the outer sides of the overflows. In the middle are (2) CL returns which I could direct any way I wish. All other returns would be over the sides. My big issue that I relized I could not ignore was the limited space behind the tank (14") Any bulkheads out the back with pipes would just be asking for me to bump into them and cause problems. So as much as I would have liked external overflows or back wall connections it really would not work and I regret the hassel later on down the line.

Any comments or suggestions welcome. Thanks,

Jon..........

 

[dannieboiz]

Why not do an external over flow? Save all the real estate inside your tank.

 

[bheron]

Hey Jon, good luck! Let me know if you have questions as I just completed my 210 inwall setup.

Link here: http://www.reefcentral.com/forums/showthread.php?s=&threadid=582988

 

[Jon]

Progress Update.............

Tank room wall framed

Sheetrocked

Painted

Tank installed

 

[Jon]

A little more about the tank......


Tank Specs:
Built by Miracles Aquarium in Canada
250g - 96"l x 24"w x 25"h (trim front to back down by 1/8")
3/4" Starphire front panel
5/8" bottom (tempered)
5/8" all other panels
Internal euro on bottom - 2" all around
Top edge euro (4" back, 2" front, 4" sides) fully polished
All edges machine polished
(1) internal back/center overflow - 14"l x 6"d - clad w/ black acrylic 1/4"
(10) holes total - (2) for 2" bulkhead & (8) for 1.5" bulkhead

Tank Crated in Truck

Looking at the white packing foam through starphire

Looking at the white packing foam through back float glass

Tank stitting on the stand

 

[Jon]

Question ?????????

On both sides of the tank it would appear that it only sits on the foam along the back and front of the tank, not in the middle. Notice below the gap between the foam and the stand. It's about 1/8" gap and I can move the foam up and down.

Is this something to be worried about?

Front and back edges are fine.

Thougths / Comments ?????????????

Jon..........

 

[bheron]

Hey Jon - looks great! love the framing and trim work. awesome tank. my only thought about your question is that maybe wait until there's more weight on the tank - like water - maybe that will balance things out?

 

[Rock Anemone]

Looking great so far, can't wait to see more!

 

[Sonia Taro]

Where is the picture of you with your hand stuck under the tank as we were putting it in place?????

 

[frazier]

love it.... I would kill to have a house that I could build something like that...

 

[Jon]

Oh !! and a special thanks to the number of friends that help magicaly made the tank float from the truck to the stand. THANK YOU !!

As for the picture of my crushed hand under the tank, hmm.. not sure where that picture went. We just don't talk about that anymore.

Jon..................

 

[Sonia Taro]

How about your lovely wife's hand stuck under the tank

 

[Jon]

See this foam board........ BAD !!!!!!!!!!

Don't use it. I just went and measured it under the tank and on a duplicate unused peice and I can't beleive what I found. It measures a consistant 27mm (1") along the lengths, but is thinner toward the middle, by about 3mm (1/8"). This is completely consistant what I'm visually seeing. Furthermore, the foam really is not compressing. And if is I'm only measuring about a 0.5mm compression difference between the used and unused sheets.

Just to be sure I measured the plywood and it is a consistant 18mm throughout. Also using a flat bar against the underside of the plywood I can detect no deflection or bend. It's flat and level.

So what this now means is that I need to remove the tank and replace the foam. Any suggestions on a readily availble type/brand from like home depot or lowes? I can't beleive this!!!

Jon..........