A coast to coast overflow advantages design

[EAsalty]

Google coast-to coast images and you will find images with measurements and various bean animal modifications

 

[BZOFIQ]

I see images with 10", 9", 8" 6.5" and even shallower. Not much of help there. I'm looking to hear reasoning why one went with whatever depth they did.

I think too tall a box would be detrimental because of large water volume and weight in the box. In addition, water flowing into the external box would creating waterfall effect and noise/salt spray.

Too shallow a box and the pipes may create suction noise unless they have 2 x 90'degree elbows sucking water from the bottom of the overflow.

I tend to think somewhere along the lines of 6.5 - 8" and the most, I'd like some confirmations before I proceed.

 

[EAsalty]

I am having a custom 150 gallon rimless tank built right now and . . . now you have now have me worried. :-)

My tank is 60x25.5x24, my external CTC runs the entire back wall, and the external overflow is 5 inches front to back and 10 inches deep, per my desire to add a lid over the overflow. The designer originally indicated 5 " front to back and 6" deep with an open top and added the extra inches to keep the pipes lower in the box to permit using a cover. He said the external portion would hold the water with no problem. In the CTC external box, I am using Bean Animal. I have five holes being drilled with the three in middle at 1.5" and 1" holes on each end for return pvc pipe using 90s with siphon holes and ¾” loclines to go through the teeth rather than over the top due to the lid.

Yes, I have read the yeas and nays about using teeth or just a smooth overflow. However, in my current 90 gallon durso system with 11" overflow box with teeth, everything is fine outside of the occasionally gurgle and burp :-) so I will be thrilled with a 60" CTC with teeth! I also using clear silicone rather than black for my seams, which is another nerve-racking decision! I am still a noob in my 4th year so yes I still make many mistakes every week if not every day!

Reading too much in forums drives me crazy considering for every positive- there are two negatives! In this hobby, we have to make a decision and stick with it, whether right or wrong.:rolleyes:

 

[User1]

I also have a tank from Concept Aquarium from Calgary. However, both yours and mine are modified Coast to Coast because of the slots. You want a smooth weir, not the grooves.

 

[Ryan Doolittle]

I am confused on not breaking the water tension to make skimmer more efficient. How does this help? Especially when the tension will break when it goes down ghe overflow pipes.

 

[Matt Carden]

I have a 5'x2'x2' SCA 150 with a central internal overflow with plumbing going through bottom of tank. I have regretted everything about the setup except for the price. I've been wanting to transform into a Peninsula with a coast to coast external overflow. Also the tank comes with 3 1" bulkhead holes so I have no choice but to have Herbie drain with one 1" return. If I transform into coast to coast, I will be able to accommodate two 1" returns and a bean animal drain. I recently moved from Augusta, GA to Detroit. During the move, my daughters skateboard shifted and broke the top of my side panel of the tank.

I've been thinking that now would be a good time to modify the tank for coast to coast. I was thinking that I could carefully remove th broken piece. Take it to a glass shop and have it cut down to be a smooth Weir. Then have some new 1/4" glass cut for my external overflow box. One problem I see is that the tank is eurobraced so after this modification I would only have 3 sides of eurobracing. Maybe I could eurobrace that side just below the water line. Or maybe an internal overflow box could perform the structural function of eurobracing.