Tank build advice

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Hi members.
OK so I have now decided to build my own tank. The dimensions for the tank are as follows are as follows
Front and back 1.4L x 600H
Side (outside dimensions) 600x600
Glass thickness 10mm ( got a good price on all the glass)
Sump dimensions are as follows
Front and back 1.2L x 450 H
Sides 450x 450 ( this is an existing tank I'm converting, 7mm glass)

My questions are as follows, I'm considering 2types of over flows
Corner over flow built in or coast to coast along the intire back of the tank ( bulk head type) built in. What would the experts out there recommend?

The second question is what size holes would I require? ( would like them to be predrilled) and how many?

Last question for now is can I have my return water plumbed into to over flow but exiting obviously outside the overflow, I'd like to try this to keep all the plumbing hidden in the over flow box.

Ohh and my sump tank...will the above size be ample for the tank?
 
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Hi Mozzie,

First off the tank dimensions are a little off for a marine tank, Marine tanks just look weird without plenty depth in terms of front to back, don't get that confused with tank height. If I were you I would have the guys cutting your glass got to at least a 700mm depth/width your height seems spot on at 450.

upload_2016-5-5_15-39-51.png


That's all you really need for the overflow, if you want to keep it neat simple and maintenance free, I've been running mine like this for the last 6/7 years. Work out your water height, work out your drain inlet height jam the calculations together and you're sorted. Drill a hole in the back of the glass, If you have sufficient sump space you could even leave the join highlighted in orange unglued thus allowing to optimize you water height to different levels based on the angle of the 90 degree bend left and right movement:
upload_2016-5-5_15-44-0.png


Sizes I would recommend going 2" or 50mm, cheap and easy to find.
How many; I've been running a single overflow since I started with the hobby. But some people prefer to have a fail safe.

I have only ever flooded my lounge floor 3 times, and none of the times was because of the overflow. Most Salt water keepers will have had at least 5 floods by the time they reach gatvol or a par over novice, like me.

Sump sounds like a good size, remember your water height will always run higher than your overflow pipe and the sump needs to accommodate for the excess water in the return lines as well as in the display tank that needs to run down into the sump once power is lost or you have maintenance on the return pump.

Remember this excess water quantity above sump and display tank height is based on the volume/speed of your return pump, and the efficiency of your drain assembly.

Hope this helps.
 
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Zippy thanks for your info. Zippy the tank hight is 600W and 600 H, so you would recommend 700H?
I will also be bracing button and top of the tank...100mm strips of 10mm glass right round the bottom and on the top I will brace both ends with the same strips as above and a 300mm strip in the centre
 
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Zippy thanks for your info. Zippy the tank hight is 600W and 600 H, so you would recommend 700H?
Think what he mend was 1400 x 700 x 600 I personally will not make my tank any deeper than 550mm as I got short arms and strugle to reach the bottom of the tank... will say size will differ from person to person.
1400 x 600 x 600 with water on 550 will work 100% imo
 
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Haha thanks Express! Shit that just saved me from going back to the drawing board
 
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With the over flow thing, I was liking the corner over flow but with having to brace the tank I'm forced to go coast 2 coast along the inside of the tank,full length of the back. Would you say 2x 50 mm holes would be fine for drain or 2-3 smaller holes?
 
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1400 length - Left to Right
700 Width - Back to Front
450 Height - Top to bottom.

Height at 450 allows for a lot more lighting options.
 
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Ahh OK, now I got ya zippy.... Think I'll cut it down to 500H so water level will be at approximately 450
 
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Damn there is alot to take into consideration before the build, Internet doesn't really help....just confuses the matter
 

RiaanP

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I would stay with a deeper tank. 600 to even 750 mm Height - Top to bottom.

Rockstack would anyway help with getting corals closer to the lights.

And on most tanks, check where does the fish swim? Most of them hang around the bottom half of the tank. Only going to the surface when they are fed, and then only some. They do not hang around the top and wait for birds to take them out. OK, we do not have sea gulls flying around in our houses, but the fish do not know that.

750mm is also the deepest I would go. Although 800 does look good. And is doable. But then you are at the limit of your arms reach, picking anything up from the substrate becomes a mission with even your armpit wet. And on a deeper tank you do need better lights, which cost a lot more.

With the internal elbow fitting as overflow. You are limited to maximum flow rate you can achieve via your sump. If you use a 6000+ L/h pump as return, your head height would be too much, allowing smaller fish like young clowns to go over. Seen that. And a lot more difficult to put a guard on it as the flow rate suction would anyway trap a small fish, killing it. Seen that.

The total length of the overflow should be as long as possible. Be is a box or coast to coast or triangular corner "box". For a box, calculate both sides of the overflow. Reason for this recommendation is that that would give you a lower water head height in the display. Leading to less water draining to the sump on a power failure. Not enough "suction" to pull small fish over, although they can still jump. And even with a long overflow comb, the waterflow through the comb will not be strong enough to trap a small clown.
 
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Riaan thanks for that advise, what I'm thinking of doing is an over flow of about 90% of the back length of the tank with 3 x drain holes +- 32mm holes leading into the sump. The other 10% of the back will be where my return water comes back into the tank. The overflow will be a coast to coast internal. The question is it advisable to drill 5 holes in the top of the tank. Please advise what you think of this idea. Much appreciated
 

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