Current C2C Techniques

[ataller]

I have been reading into the best ways to do a coast to coast overflow. Mine will be built out of glass, going to use a box not the angeled version.

I wan't to keep the box as skinny as possible. Do I need to use 90 degree elbows in the bulkheads? I read somewhere about cutting a piece of PVC into a C shape, instead of the full O, and using that instead of a 90. Does this work? If I do not have to fit in a 90, I should be able to make the box skinnier (front to back) and reduce the shadow it casts.

What is the current thinking on how colour the C2C black. Can I paint the glass with anything that is safe for a reef tank? Do I order a black piece of acrylic to side inside the box?

Any other tips on a C2C?

Thanks!

Adam

[uncleof6]

Sure, put it on the outside of the tank. NO shadow worries, and no weird plumbing pieces. ;)

Jim

[ataller]

I'd like to but there is a trim on the tank. I would hate to take the trim off and crack the tank.

Then once the trim is off I have to eurobrace it.

Also have to find someone to notch the back wall for the overflow.

All of which isn't going to happen unfortunately.

[ataller]

Going to have to bite my tongue I think.


Just found a picture of this here on RC. A small internal C2C that leads to an external box.

Anyone tried this does it work? Do the holes in the back tank wall need bulkheads or can they be left bare?


http://farm4.static.flickr.com/3457/3994599624_cf19a6e05c.jpg

Adam

[uncleof6]

Going to have to bite my tongue I think.


Just found a picture of this here on RC. A small internal C2C that leads to an external box.

Anyone tried this does it work? Do the holes in the back tank wall need bulkheads or can they be left bare?


http://farm4.static.flickr.com/3457/3994599624_cf19a6e05c.jpg

Adam

I would center it on the back just because I like symmetry, however you would be very surprised how much water will flow out those two 2 3/4" holes, with an inch or two of head pressure on them.......oh incidentally, that will work, and you won't need bulkheads in the holes. (I won't always tell you everything in the first post.... see if you will go look for it... seemed to have worked.... :D

Just remember with a c to c, you need a dead level tank.

Regards,

Jim

[ataller]

Agreed, I like symmetry, no reason to put the box off to one side.

My drains are going to be 2, 1.5" dursos, I only expect to have about 1000 GPH max through them, using two for redundancy. Do you think the two 3/4" holes will be able to handle it, or should I drill two 1 inch holes in the back of the tank.

Adam



I would center it on the back just because I like symmetry, however you would be very surprised how much water will flow out those two 2 3/4" holes, with an inch or two of head pressure on them.......oh incidentally, that will work, and you won't need bulkheads in the holes. (I won't always tell you everything in the first post.... see if you will go look for it... seemed to have worked.... :D

Just remember with a c to c, you need a dead level tank.

Regards,

Jim

[1DeR9_3Hy]

I would center it on the back just because I like symmetry, however you would be very surprised how much water will flow out those two 2 3/4" holes, with an inch or two of head pressure on them.......oh incidentally, that will work, and you won't need bulkheads in the holes. (I won't always tell you everything in the first post.... see if you will go look for it... seemed to have worked.... :D

Just remember with a c to c, you need a dead level tank.

Regards,

Jim

What is the correct way to level a tank?

[ataller]

As far as I know you shim the stand, not the tank.

[uncleof6]

That is correct.

Jim

[uncleof6]

Agreed, I like symmetry, no reason to put the box off to one side.

My drains are going to be 2, 1.5" dursos, I only expect to have about 1000 GPH max through them, using two for redundancy. Do you think the two 3/4" holes will be able to handle it, or should I drill two 1 inch holes in the back of the tank.

Adam


You would be doing yourself a big disservice by using 2 dursos, because you will not get 1000 gph through the both of them together (more likely 640 or less) without noise, bubbles and reliability issues. you want 1 1.5" full siphon (good to go for 2500 gph +) 1 1.5" durso good for maybe 320 gph (reliable, quiet without bubbles) and 1 1.5" emergency. You could get away with 1.25" stem to stern plumbing for 1000 gph. 1" plumbing maybe.

You want large holes in the back of the tank for through put from the wier to the standpipe box. To avoid sumptin gettin stuck in them. How much will a single 2.375" hole (since you have the diamond core bit anyway for your standpipes) would be ~1860 gph with 1" head pressure on it. With 2" head pressure on it ~2700 gph. A 1" hole w/1" head pressure ~300 gph, and 480 gph with 2" head pressure (these are rounded off in the math to nearest whole numbers) they come out to X.xxxxxxxxxxxxxxx type numbers for gpm. You want the capacity of the holes to be far greater than the flow rate.... think it about it for just a bit. This is just a circular hole with no plumbing.

Jim

[ataller]

Alright I have a new questions now.

For the internal section of the overflow, do I do 1 piece of glass set at an angle or do I make a small box with two pieces of glass?

Is there an advantage of one over the other?

One piece of glass keeps it more simple. Is there a distadvantage though?


Adam

[ataller]

One more question.

If I am drilling holes for bulkheads in the external box, a 1.5" bulkhead needs a 2.5" hole. If my box is 5" deep, then there will onl be 1.25" of glass on each side of the drilled holes. Is this enough?


Adam

[uncleof6]

Alright I have a new questions now.

For the internal section of the overflow, do I do 1 piece of glass set at an angle or do I make a small box with two pieces of glass?

Is there an advantage of one over the other?

One piece of glass keeps it more simple. Is there a distadvantage though?


Adam

There is no advantage to angling the weir, other than it only uses one piece of glass. It is nonsense if you ask me. So don't ask me.:D

Jim

[uncleof6]

One more question.

If I am drilling holes for bulkheads in the external box, a 1.5" bulkhead needs a 2.5" hole. If my box is 5" deep, then there will onl be 1.25" of glass on each side of the drilled holes. Is this enough?


Adam

If the bulkhead you want to use needs an 2.5" hole, then you are spending more on bulkheads than you really need to. The black ABS type bulkheads are fine-- if you install them correctly, and use a 2 3/8" hole. 5" deep is ambiguous, and can refer either to height or width.

Generally, I use 5" wide external boxes, with 2 3/8" holes in them (3 - 4 of them) and use 9mm glass (sometimes 12mm depending on length) to make the boxes. The inside box can be 6mm. As long as your plumbing is supported, there should not be a problem.

Regards,

Jim