Silent and Failsafe Overflow System

[uncleof6]

Can this be used for a HOB overflow, without drilling the tank?

It can be yes, but only really makes sense to use the siphon and open channel for self adjustment reasons. The likely failure point is the siphon tubes that go over the back of the tank, which would render the whole thing rather useless. Redundancy in the over the back tubes would be a really good idea.

Jim

 

[pmoneyt]

Hey uncleof6 I want to ask you a few question about added a C2C in my 180 but I will have to cut out the over flow boxes. My plan is to use the two 1 1/2 pipes for the open channel and the siphon, and the two 1" and the emergency drains.

I would have to drill the bottom of the C2C as it will internal. However the brace on the bottom of the tank worries me. so I was planning on cutting a piece of glass and gluing it in that place unless its not needed.

What size thinkness of the glass should I use? Does this make any sense? If not please PM me as i don't want to go off topic in this thread.

 

[Bzar]

quick question. Can the stand pipes (the length between the T's and the outlet into the sump) be short, say around 1' - 2' ?

Thanks.

 

[Lanimret]

Looking for some advice. I'm been struggling with this decision for a week now and my project is stalled.

Here is a picture of the side of my tank (it's standing on end) and my half finished overflow box (I'm waiting for some bulkheads to finish the bottom) resting in the location it will be attached.

What I need to figure out is what kind of opening to create in the tank wall to let the water through.

I've considered:

Drilling holes - Seems like the worst option, and most likely for cracks.

Cutting vertical slots - Seems like a good option, but I'm having a tough time coming up with a way to cut these where you are not starting from the edge.

Cutting horizontal slots - Easiest. I'm thinking a 15" long slot straight across 3/4" high but broken up into 4 sections to maintain tank strength.

Any suggestions? I need enough opening to move the water without compromising the tank. I'm going to be moving about 600gph and it is a 100g tank.

 

[malcomm]

the caps are for cleaning purposes not needed but highly recommended.

Aah, ok so they aren't glued on.
Glad I asked first

I thought it was a vacuum effect in there.

Many thanks
Malcom

 

[malcomm]

Has anyone Teed off the siphon pipe to direct feed a skimmer?
Did a search but couldn't see anything.

I'd be running 1" from the bulkhead through to the sump and T into a 3/4" for the skimmer. Ball valve on both branches

Cheers
Malcom

 

[teesquare]

Aah, ok so they aren't glued on.
Glad I asked first

I thought it was a vacuum effect in there. If you are thinking of the siphon - YES - there is a vacuum effct. It needs to be sealed. Silicone will work, and will allow you to remove if you ever need to clean in there.

Many thanks
Malcom

 

[uncleof6]

Has anyone Teed off the siphon pipe to direct feed a skimmer?
Did a search but couldn't see anything.

I'd be running 1" from the bulkhead through to the sump and T into a 3/4" for the skimmer. Ball valve on both branches

Cheers
Malcom

Have not heard of or seen anyone that has actually gone so far as to implement this idea. It is not predictable how the balance and function of the system would be affected. If you do implement it, you would probably be the first, though MANY have asked about it. Personally, unless the skimmer is designed to be fed this way, it will more than likely, reduce the skimmer performance.

Jim

 

[teesquare]

Has anyone Teed off the siphon pipe to direct feed a skimmer?
Did a search but couldn't see anything.I have never seen it work well. ANY variation in water column height will screw up the skimmer functioning efficiently

I'd be running 1" from the bulkhead through to the sump and T into a 3/4" for the skimmer. Ball valve on both branches

Cheers
Malcom

 

[malcomm]

Have not heard of or seen anyone that has actually gone so far as to implement this idea. It is not predictable how the balance and function of the system would be affected. If you do implement it, you would probably be the first, though MANY have asked about it. Personally, unless the skimmer is designed to be fed this way, it will more than likely, reduce the skimmer performance.

Jim

Its an external recirc skimmer which would normally have a pump feeding it from the sump but a 3/4 siphon would have more than enough flow for it. Just wondered if it would stuff up the flow to the sump. Guess it wouldn't hurt as the pipe will carry its max and that's it

I'd think the pipe to the T should be increased in size a bit but I've already drilled the holes in the tank.
Would like to hear anyone else's experiences...

malcom

 

[BeanAnimal]

quick question. Can the stand pipes (the length between the T's and the outlet into the sump) be short, say around 1' - 2' ?

Thanks.

Gravity is what drives the flow. The shorter the standpipes, the less gravity helps and the larger the pipes have to be. How much flow are we talking about?

 

[BeanAnimal]

Aah, ok so they aren't glued on.
Glad I asked first

I thought it was a vacuum effect in there.

Many thanks
Malcom

Thet MUST be air tight (other than the air inlet tubing for the open channel fail-safe).

Screw on caps with teflon tape or paste are specified in the plans

 

[thebanker]

It can be yes, but only really makes sense to use the siphon and open channel for self adjustment reasons. The likely failure point is the siphon tubes that go over the back of the tank, which would render the whole thing rather useless. Redundancy in the over the back tubes would be a really good idea.

Jim

Are you saying only use the siphon and open channel tube, but no emergency tube? I know you need all three to make this concept work, but when it's applied to a DIY overflow box, the physics isn't quite the same.

 

[uncleof6]

Are you saying only use the siphon and open channel tube, but no emergency tube? I know you need all three to make this concept work, but when it's applied to a DIY overflow box, the physics isn't quite the same.

The physics do not change. What changes, is the failure point. To get water out of the tank to the external box, (with an undrilled tank) you gotta use an over the top siphon tube, right? Anything that would plug up the siphon or open channel in the external box, (which would kick in the dry emergency) will plug up the over the top siphon tube first, before it gets to the siphon or open channel. Water level in the tank would rise, but the emergency would not kick in. Flood time.

Jim

 

[GrayWhale]

Lanimret;

A single continuous horizontal slot will give you the thinest layer of water passing over the weir and therefore the most efficient surface skimming. I wouldn't worry too much about tank strength. That end panel is already the stiffest one in the tank. The overflow box will act like an external eurobrace and add even more strength.

Use a router with a 1/2" plunge bit to cut the slot. If you then ease the edge with a roundover bit the water will flow smoothly over the weir and contribute to the silence.

 

[Lanimret]

Thanks!

I actually talked to Acrylics directly and did something similar.

I made a 3/4" by 6.5" jig out of some scrap wood. Used a 3/4" butterfly bit and cut a hole, then used a 1/2" straight bit with a top collet and traced the jig. I made two slots next to each other with 3/4" of acrylic left in between.

It came out excellent, I am very pleased. I will take your advise and use a round-over bit as well, that's a good idea.

I made the hole 3/4" for a few reasons, one because I figure it gives me a little extra water flow capacity (sticking my arm in the tank for instance) and frankly it was easier to cut with the bit's I had available.

Problem is now that Acrylics is telling me 1/4" cell cast Acrylic isn't good enough for the overflow. I'm debating buying some 1/2" or building some extra reinforcements in using the 1/4".

 

[Bzar]

Gravity is what drives the flow. The shorter the standpipes, the less gravity helps and the larger the pipes have to be. How much flow are we talking about?

Hmmm ya that's what I was worried about. ATM I believe I'm pushing around 800gph (1000gph max) through a system with the exact measurments of the original....1" bulkheads converting to 1.5" standpipes. The valve on the syphon channel is dialed way down...near shut it seems some days, so maybe it's even less then 800gph.

Reason I'm asking is because of a new frag system I'm setting up right behind the tank. As it stands my display sits flush against a wall, the pipes from the overflow go through the wall into a sump in the next room, then pumped back up through the wall from the sump.

I'm thinking of putting some frag tanks behind the display on the other side of the wall above the sump. Idealy I'd like the display to overflow into the frag system, then the frag tanks into the sump, then back up into the display through the wall.....that way I don't need another pump to push water up to the frag system. Only problem is that the frag tanks (while they are shallow, only 11") would be idealy at least 2' higher than my sump which causes the need to shorten the stand pipes. This would cause me to have stand pipes of only 1' - 2' (approx). If it's a bad idea then perhaps I'll just have to bite the bullet and pump into the frag tanks....more power cunsumption, another cost, but if it's gotta be, it's gotta be.

What ya think?

Thanks for the help.

 

[BeanAnimal]

1' to 2' of drop is fine... a few inches is another story

 

[Bzar]

@BeanAnimal: thanks for the great help once again.

 

[rpeeples]

Couple of quick questions for ya bean and co....

I am setting up a frag tank (50G) which will tie into my current setup (240G display/ 100G Sump / 30G Fuge). I plan on running no more than 500 gph through the overflow of the frag system.

Can I run 1" plumbing using only a siphon and emergency line? I know you used 1" bulkheads to 1 1/2 " but since this setup is not required to handle more than 500 GPH I thought 1" would be sufficient?

Thanks