Project External Glass Overflow

[NuclearReefs]

LOL steve,, my dremel is variable,, you might wanna borrow one like that from someone .. try it out ..

Nathan

 

[mmmmsushi]

Why not cut at 30,000? Heat? I was cutting at both but I like 30,000rpms better. It ended up cutting faster but I went through a couple bits.

 

[steve68]

i have the same dremel i used it to cut holes in my 55 using the same bits it took 2 long thats why i went with the rotozip bit & it cuts in to the glass with no problem, i just did a 10x1 inch slot on a 36 bow for a friend & it went right through no problem,once u see how easy it is to cut with the roto bit there is no need for the dremel unless u are doing 10 gallon tank's

 

[steve68]

& yes i rather have the bit brake then the glass allways buy a couple just in case.

 

[Tunjee]

It seem as though jury is still out regarding risk involved slotting large tanks in the rear (long) glass. I practiced today on a scrap piece of 3/8 inch glass that I got at the glass shop. The tile bit, a Craftsman "dremel" and a trickling garden hose worked perfectly and fairly quickly. I was planning to slot a 90 aga. I was going to slot the tank toward one end rather than in the middle. I was planning one 10"x1.5" slot or two smaller ones, with the addition of some black acrylic on the inside. Do I read this thread correctly, that such a plan may meet with diaster once the tank is filled with water? Slotting the end is not an option in my situation.

Thanks for any feedback.

Bob (maybe a wier is the way to go in my case)

The TOTM a few months back 300g. The back piece of glass had a slot cut out with eggrate for a strainer. I dont know if the slot was factory or laser cut or what sorry. Here's the link http://www.reefkeeping.com/issues/2004-04/totm/index.htm

The overflow.

 

[steve68]

nice that looks familiar

 

[braymil]

What about this idea? (RE: cutting the back glass of a 90 aga)

Individual 1/4" slots cut in the glass for overflows. I propose two overflow areas - one toward each corner of the tank. The overflows areas would start 3 inches in from the side panel glass. Each overflow area would be 5.5 inches wide. The overflows would consist of eight 1/4" slots with 1/2" of glass between each slot. The slots would be 1.0 - 1.5" tall and well rounded at the top and bottom. The top of the slots would be no less that 1/2" from the top of the tank and preferably and inch from the top.

Is this idea going in the wrong direction. My thinking is as follows. This idea makes smaller slotted areas on the back of the tank but gives enough total slots for appropriate throughput. My current HOB skimmer has 11 slots total. This proposal provides 16 slots.

Also, this idea moves the modified (i.e. cut) glass away from the center of the back glass. I suppose the center of the back glass is under more weight stress than the edges. This is because it is further away from the glued side walls which offer support.

I can flow test this tank in a concrete floor, sump equipped basement for a good month if need be, but if the above thinking is flawed, I would like to know. My alternative to all of this is the wier on Melev's site. I am tired of dicking around with the U-tube siphon.

Thanks again for all your input and critical thinking.

Bob (still going back and forth)

 

[steve68]

that will work the only reasond i did longer slot is because it was faster & with the acrilic u woulnt see the overflow box, if u are willing to put the time in to it & make them just like u said i see no problem,post pictures when u finish it.

 

[braymil]

Actually, I would prefer to notch the top of the tank (1.5" x 12" or so) and then cover with slotted acrylic. It seems that this idea is risky in that it creates a weak area in the large back glass - prone to cracking when filled and under stress.

I am guessing that individual slots, spaced 1/2' apart, and set down from the top edge of the tank, and moved away from the center of the back panel as well as located in two smaller areas will minimize the weakening of the back glass and thus the cracking risk.

I am not sure I am going to do this, but I will keep you posted. I hope you and others will continue to offer any advice you can.

Bob

 

[jims47]

This is a great thread! I have a 5 gal. acrylic Nano I was going to bottom drill. This will be much easier especially since it's acrylic. I have a couple sheets of black acrylic that will work great for the box. Thanks for the great idea. Wish I could do this on the 30 but I would have to do it with the livestock etc, would probably end up with a big mess on the floor,lol.
Jim

 

[indianafishkeeper]

I just tried this on a 29 gal. tank I bought from walmart a few years ago. The outcome was a whole bunch of pea sized pieces of glass scattered all over my garage. So just a warning to those who buy tanks from walmart, they might be tempered.

However, I figure this is no big deal, as I'll go get a piece of glass custom made from my local glass company and just replace the whole back sheet of glass with the new one. And this time I'll have the glass company cut out the back.

 

[Bobby417919]

Tunjee Very nive job

I have quick question. On page 8 is a pic of your tank, how is the return set up.

Thank You
Robert,

 

[Tunjee]

Bobby:
Thanks. It goes from the pump to a SCWD then to an overhanging return in each corner. My scwd is noisy. Maybe Oceans Motions squirt would be better?

 

[NuclearReefs]

Tunjee,, You should put a link to your home page in your member line .. show off that tank more..

Nathan

 

[Tunjee]

hcrk finaly replied to me about his external overflow:


quote:
--------------------------------------------------------------------------------
Originally posted by Tunjee
Tank is magnificant! How was the slot cut out for the external overflow? Laser, water jet or ground out with a rotary tool. Is there eggrate infront of the intake?
--------------------------------------------------------------------------------


The "slots" are actually three 2 1/2" round holes that were ground out with a diamond rotary drill.

An overflow box is also mounted on the inside of the tank. The internal overflow has plexiglass "teeth" at the top which can be mechanically adjusted to control height and flow.

 

[Tunjee]

Heres a pic of it.

800gallon tank of his is truely amazing.

 

[Tunjee]

Tunjee,, You should put a link to your home page in your member line .. show off that tank more..

Nathan

Sorry I dont have a homepage, just use photobucket.com to host the pics and then post them here. Maybe I should try making a webpage, sheesh where to start I dont know. How bout some new tank pics?

 

[sde219]

Sorry for asking a question that clearly somewhere in this 20 page thread. Those of you who attached an acrylic sheet with holes cut out of it - how did you attach the sheet?

Thanks
Steve

 

[impur]

I think just silicon would work. The pressure of the water in the tank would keep it pushed against the back glass so there would be no worry about the silicon bond coming undone.

 

[Tunjee]

Silicone is used to hold the acrylic to the inside back glass. It might help in case the glass cracks, it should buy me some time between tank replacement. You never know when Murphy's Law will show up.