Glass? Or Acrylic? For an overflow box.

[rhickman17]

Hello ladies and gents,

This overflow box isn't going on a reef tank (unfortunately) but I am stealing an idea from the reefing community . I'm going to be setting up a Herbie overflow on a 6 foot freshwater tank and I'll be drilling the tank myself. My question is whether I should stack the drains one on top of the other on one side of the tank and use a vertical box OR if I should drill the holes horizontally beside each other along one pane of glass and use a horizontal box.

Following the community input, the next big question is glass or acrylic for the overflow? I know acrylic doesn't bond well to glass, but I have seen threads online about people having some degree of success in the past with acrylic bonded to glass as their internal overflow box but I'd rather do it right and not have to worry about it.

I've also seen threads where people have built acrylic boxes and then sealed them using a gasket between the bulkhead and the inside of the box and then another bulkhead between the outside of the box and the glass of tank itself, if that is necessary I can do that too but I may need different bulkheads than the ones I've already ordered.

Thanks in advance everyone

 

[fishgate]

The primary purpose of the in-tank overflow box is the surface skimming it provides which saltwater tanks benefit greatly from. To this end, the more skimming you can do (coast to coast) the better. For freshwater, I would suspect it would also benefit from surface skimming.

You could make the entire thing out of glass and then only need 2 pieces, the front and the bottom. Then silicone it to the back of the tank. You could also make it out of acrylic and then attach it via the bulkhead gaskets like you mentioned. One of my tanks has an aftermarket acrylic overflow attached in this manor. The only method I would not do is 2 pieces of acrylic attached to the tank like the first example in glass due to long-term adhesion properties of silicone and acrylic.

Whatever method you choose will require you to drill the tank. 3 holes for Bean style is preferred and you could add additional holes for the return or do an over the top return.

 

[mcgyvr]

In case you didn't know what a bean overflow (drain system really) is..
http://www.beananimal.com/projects/silent-and-fail-safe-aquarium-overflow-system.aspx
Thats a bean with a coast-coast overflow box.. that can be internal or external..
It is hands down the best system..

and unless you are securing the acrylic box with the bulkheads you are always best to use glass for glass tanks and acrylic for acrylic tanks to ensure proper adhesion/securement..

 

[lmm1967]

Coast to coast acrylic overflow installed with normal silicon. Holds fine. I wouldn't do it someplace where a leak would cause a big problem but it works fine for internal overflow


Sent from my iPhone using Tapatalk

 

[rhickman17]

The primary purpose of the in-tank overflow box is the surface skimming it provides which saltwater tanks benefit greatly from. To this end, the more skimming you can do (coast to coast) the better. For freshwater, I would suspect it would also benefit from surface skimming.

You could make the entire thing out of glass and then only need 2 pieces, the front and the bottom. Then silicone it to the back of the tank. You could also make it out of acrylic and then attach it via the bulkhead gaskets like you mentioned. One of my tanks has an aftermarket acrylic overflow attached in this manor. The only method I would not do is 2 pieces of acrylic attached to the tank like the first example in glass due to long-term adhesion properties of silicone and acrylic.

Whatever method you choose will require you to drill the tank. 3 holes for Bean style is preferred and you could add additional holes for the return or do an over the top return.

How thick would the glass have to be to make it a coast to coast overflow on the 6' tank? 1/4"? 3/8"? I know about drilling the tank I have drilled a few previously, I didn't know about the Herbie or the Bean Animal the last time I had set up a tank so now that I'm getting into a new setup I want to silence my setup!

Either way the best way to drill them is horizontally aligned correct? The tank bottom is tempered so I am going out the back pane or one of the side panes of glass.

 

[rhickman17]

In case you didn't know what a bean overflow (drain system really) is..
http://www.beananimal.com/projects/silent-and-fail-safe-aquarium-overflow-system.aspx
Thats a bean with a coast-coast overflow box.. that can be internal or external..
It is hands down the best system..

and unless you are securing the acrylic box with the bulkheads you are always best to use glass for glass tanks and acrylic for acrylic tanks to ensure proper adhesion/securement..

Thanks, ya I do know what it is, I wasn't too keen on building the Bean Animal just due to the fact I don't have a tap set to inset the airline in the cap on the second drain. If I could just drill the top of the cap and silicone the airline in I would probably be more inclined to go with the Bean Animal because I do know and recognize it is the superior drain system.

 

[rhickman17]

Coast to coast acrylic overflow installed with normal silicon. Holds fine. I wouldn't do it someplace where a leak would cause a big problem but it works fine for internal overflow


Sent from my iPhone using Tapatalk

Okay, thanks for the input, I have had a few testimonials on other sites about people doing acrylic to glass. It just concerns me with all of the NEGATIVE input I have seen on the topic as well.

 

[fishgate]

How thick would the glass have to be to make it a coast to coast overflow on the 6' tank? 1/4"? 3/8"? I know about drilling the tank I have drilled a few previously, I didn't know about the Herbie or the Bean Animal the last time I had set up a tank so now that I'm getting into a new setup I want to silence my setup!

Either way the best way to drill them is horizontally aligned correct? The tank bottom is tempered so I am going out the back pane or one of the side panes of glass.

I'd go at least 1/4" glass. And build a platform (2x4s) to hold it in place while you apply the silicone and let it dry. If you are having the glass cut, see if they can and what they charge to temper the glass.

And the acrylic siliconed to glass will "hold" but will also eventually leak. Once it leaks, if you have a power outage your tank will drain down to the level of the leak, which will probably overflow your sump.

Drill your holes horizontally across the back of the tank. The top of the full siphon drain should be lower than the bottom of the open channel drain. I'd go at least 1/2".

FYI: It is not a big deal to tap in the fitting on the top, it is not a pressure fitting so you just need to drill the hole and attach it with an o-ring if you can screw it in and if you made it too large, just silicone it in.

 

[rhickman17]

I'd go at least 1/4" glass. And build a platform (2x4s) to hold it in place while you apply the silicone and let it dry. If you are having the glass cut, see if they can and what they charge to temper the glass.

And the acrylic siliconed to glass will "hold" but will also eventually leak. Once it leaks, if you have a power outage your tank will drain down to the level of the leak, which will probably overflow your sump.

Drill your holes horizontally across the back of the tank. The top of the full siphon drain should be lower than the bottom of the open channel drain. I'd go at least 1/2".

FYI: It is not a big deal to tap in the fitting on the top, it is not a pressure fitting so you just need to drill the hole and attach it with an o-ring if you can screw it in and if you made it too large, just silicone it in.

If I go coast to coast I will be having the glass cut, if I don't have it cut, I will be taking apart a 20-30 gallon aquarium and building the box myself (my preference personally).

If you silicone it in it would work the same way correct? I'm leaning toward a Bean Animal now. Same as what happened the last time I planned a tank... started thinking Herbie.. Leaned back toward Bean Animal and ended up deciding on Bean Animal. Never got that tank setup but at least I had the plan and the parts back then lol.

 

[mcgyvr]

Yes the airline works just fine if siliconed or epoxied in place..
Just seal it up well and its not an issue...

 

[rhickman17]

With regard to drilling the holes, I'm struggling to understand how you expect to have a full siphon and then a small amount of water trickling down the open channel. Do you adjust the gate valve on the full siphon pipe to the pipe where it is in full siphon AND also allows a small amount of water to cascade down the sides of the open channel at the same time?

If my holes were drilled horizontally how would I get the top of the siphon drain to be half an inch lower than the bottom of the open channel drain? Wouldn't that mean I would have to drill the one hole lower down the glass than the other?

 

[mcgyvr]

Do you adjust the gate valve on the full siphon pipe to the pipe where it is in full siphon AND also allows a small amount of water to cascade down the sides of the open channel at the same time?

Wouldn't that mean I would have to drill the one hole lower down the glass than the other?

yes you use the valve on the full siphon to adjust the water level in the overflow box and in relation to the elbows..

Drill all the holes at the same level..
and it works its mostly just magic

 

[rhickman17]

yes you use the valve on the full siphon to adjust the water level in the overflow box and in relation to the elbows..

Drill all the holes at the same level..
and it works its mostly just magic

Lol I like magic :spin1: :spin1:

I found this on another thread on this site "First you need to measure down from the top edge of the glass, not the top of the trim. Also, the top of the weir should be 1" down from the top edge of the glass (which puts it even with the bottom of the trim on the outside of the tank. You need around a 1" water drop, from tank water level to overflow water level, and the water level needs to rise above the dry emergency inlet to purge the air from the siphon line. Running water level in the overflow is generally ~ the top of the down turned elbow. This puts the top of the elbow down from the top edge of the glass a minimum of 2", plus half the od of the elbow gives you the hole center, it is ~11/16 of an inch so figure 3/4". This puts the center for 1" bulkheads, 2 3/4" down from the top edge of the glass, or 1 3/4" from the bottom edge of the trim. This puts the outside edge of the hole, 1 7/8" down from the top edge of the glass--or around 2 3/8" from the top edge of the trim. Gives close to 3" of head pressure on the siphon, to purge the air, without overflowing the tank."

I am drilling for 1" bulkheads so does that mean I should be 2.5" from the absolute top of the tank? Once I drill then I will build my overflow box around the bulkheads. I am having a hard time visualizing all of the dimensions being thrown around in these threads. People keep suggesting going through beans thread but there is so much bickering and stuff I don't know where to look for these dimensions that have apparently been posted in there. If anyone can share some insight that would be greatly appreciated thanks.

 

[fishgate]

With regard to drilling the holes, I'm struggling to understand how you expect to have a full siphon and then a small amount of water trickling down the open channel. Do you adjust the gate valve on the full siphon pipe to the pipe where it is in full siphon AND also allows a small amount of water to cascade down the sides of the open channel at the same time?

If my holes were drilled horizontally how would I get the top of the siphon drain to be half an inch lower than the bottom of the open channel drain? Wouldn't that mean I would have to drill the one hole lower down the glass than the other?

It would be impossible to exactly tune a full-siphon drain with the return water. So you are shooting for "slightly" more than enough return water to supply the full siphon. The extra water then rises to the open channel drain and starts to trickle down. The higher that extra water rises, the more that flows down the open drain until equilibrium is established.

Where the holes are is different that where the drain openings end up. The point with the configuration that I mentioned is to be able to have a full siphon drain with no water running in the open channel. You could do it so you can't go full siphon without the open channel draining some water as well, but on mine I set it up so the start of my open channel is slightly above the level of the full siphon running at full siphon.

 

[rhickman17]

It would be impossible to exactly tune a full-siphon drain with the return water. So you are shooting for "slightly" more than enough return water to supply the full siphon. The extra water then rises to the open channel drain and starts to trickle down. The higher that extra water rises, the more that flows down the open drain until equilibrium is established.

Where the holes are is different that where the drain openings end up. The point with the configuration that I mentioned is to be able to have a full siphon drain with no water running in the open channel. You could do it so you can't go full siphon without the open channel draining some water as well, but on mine I set it up so the start of my open channel is slightly above the level of the full siphon running at full siphon.

Alright that makes sense. I ordered 1" plumbing, but after reviewing Beans threads and website it seems he only used a 1" bulkhead and then went to 1 1/2" plumbing for his drains. Is it okay to use 1" for the siphon and 1 1/2" for the open channel and emergency?

 

[fishgate]

Alright that makes sense. I ordered 1" plumbing, but after reviewing Beans threads and website it seems he only used a 1" bulkhead and then went to 1 1/2" plumbing for his drains. Is it okay to use 1" for the siphon and 1 1/2" for the open channel and emergency?

Someone just posted a really good information video :dance: on how to do a Herbie (Talks about a Bean). Check it out I think you'll have your answers.

https://youtu.be/RYhAp6GFNz8

 

[rhickman17]

He actually has what I'm doing reversed. He has a smaller diameter open pipe than his full siphon. The pump he has is almost identical to mine. I went with the 4000. I'm thinking now I'll be able to just do 1" everything and get away without having to switch from 1" bulkheads to 1.5" pipe on the open channel.

 

[Lsufan]

The good thing about having a 1.5" open channel is that it can take more flow & flunctuations in the system & still be silent. A 1" open channel can't handle much flow or it starts to get loud. U can still tune it to where u have just a trickle going down the open channel to keep it quite but any little flunctuations & it starts getting loud, or no water at all is going down it. If noise is a big factor then I would think about upsizing but if it's not then it will work fine.

As far as making a hole for the airline fitting. I left my tap at work one time so what I did was drilled a hole a little smaller then what I needed, then I took a galvanized or iron nipple & threaded it in the hole. I used a 1/2" airline fitting so I drilled a 11/16" hole then used a 1/2" galvanized pipe and screwed it in then screwed it out to make a tap. It worked out better then I thought it would.