External Overflow box DIY options. Any ideas?

[Levinson]

Been planning a new setup for a while and haven't gotten very far because of the overflow box.

I want to have the external overflow box with two drains (herbie) but I don't think I have many options.
Where I live, they don't sell pre-made external overflow boxes. I could buy them (the likes of Esshopp or Modular Marine) from Amazon (or ebay) and have them shipped here but the pvc fitting standards here are different from the US which means I have to use US standard pvc pipe and joints etc. I did find a couple of places that sell US sized pvc plumbing gear here but they were very expensive. (Plus, the duty tax for importing them will further drive up the cost).

So I was thinking about what my options could be...

1. DIY out of acrylic:
My concern would be getting the watertight seal when joining the bulkhead to the external acrylic box. I would assume it will have 2 gaskets, one inside the tank, another between the outer side of the glass and the acrylic box, with the bulkhead nut inside the acrylic box. I'm just not sure how well it will seal this way.

2. DIY out of glass:
Drill the side of the tank, get some glass panels and silcone them directly to the outer side of glass. My concern for this is if the silicone to the glass would hold the weight of not just the water but also the plumbing gear connected to it. I guess I could try to reinforce it a little.

3. Import pre-made overflow boxes from the US and spend big $$$ to buy the US sized plumbing gear to go with them.

4. Give up on the external overflow box, DIY the tall glass internal overflow corner box:
Drill two holes on the bottom of the tank, silcone two long sheets of glass in the corner of the tank. Relatively simple but they do take up quite a bit of space inside the tank.

5. Any other bright ideas????

Which option do you think would be the best? Any feedbacks are welcome.
Thanks in advance.

A little more info about the tank I have in mind as reference:
The plan is to have two display tanks both connected to a single sump. Each display tank will hold a little less than 120 liters (about 31.7 gallons) of water. The sump water volume hasn't been worked out but the size of the sump will be the same as the display tank so I would assume it would be around 76 liters (about 20 gallons). So the total water volume would be around 316 liters (83.5 gallons).

 

[Eagle_Steve]

Been planning a new setup for a while and haven't gotten very far because of the overflow box.

I want to have the external overflow box with two drains (herbie) but I don't think I have many options.
Where I live, they don't sell pre-made external overflow boxes. I could buy them (the likes of Esshopp or Modular Marine) from Amazon (or ebay) and have them shipped here but the pvc fitting standards here are different from the US which means I have to use US standard pvc pipe and joints etc. I did find a couple of places that sell US sized pvc plumbing gear here but they were very expensive. (Plus, the duty tax for importing them will further drive up the cost).

So I was thinking about what my options could be...

1. DIY out of acrylic:
My concern would be getting the watertight seal when joining the bulkhead to the external acrylic box. I would assume it will have 2 gaskets, one inside the tank, another between the outer side of the glass and the acrylic box, with the bulkhead nut inside the acrylic box. I'm just not sure how well it will seal this way.

2. DIY out of glass:
Drill the side of the tank, get some glass panels and silcone them directly to the outer side of glass. My concern for this is if the silicone to the glass would hold the weight of not just the water but also the plumbing gear connected to it. I guess I could try to reinforce it a little.

3. Import pre-made overflow boxes from the US and spend big $$$ to buy the US sized plumbing gear to go with them.

4. Give up on the external overflow box, DIY the tall glass internal overflow corner box:
Drill two holes on the bottom of the tank, silcone two long sheets of glass in the corner of the tank. Relatively simple but they do take up quite a bit of space inside the tank.

5. Any other bright ideas????

Which option do you think would be the best? Any feedbacks are welcome.
Thanks in advance.

A little more info about the tank I have in mind as reference:
The plan is to have two display tanks both connected to a single sump. Each display tank will hold a little less than 120 liters (about 31.7 gallons) of water. The sump water volume hasn't been worked out but the size of the sump will be the same as the display tank so I would assume it would be around 76 liters (about 20 gallons). So the total water volume would be around 316 liters (83.5 gallons).

I would check with modular marine and fiji cube about them building you one with metric bulk heads. I am sure Will at Fiji cube would do it, and I love how quiet his overflows are. There is still the point of shipping, but if not in a huge hurry, you could just take the slow shipping time route and save some money.

There is also the option of ordering one, as is and then just doing metric to standard adaptors. Then you could use metric all the way to the sump.

 

[NowGlazeIT]

I would check with modular marine and fiji cube about them building you one with metric bulk heads. I am sure Will at Fiji cube would do it, and I love how quiet his overflows are. There is still the point of shipping, but if not in a huge hurry, you could just take the slow shipping time route and save some money.

There is also the option of ordering one, as is and then just doing metric to standard adaptors. Then you could use metric all the way to the sump.

This was my thought too. It’s a matter of getting the metric bulkheads ordered in and telling modular marine the fab sizes. I asked MM to cut holes for 1 1/4 bulkheads. The owner only asked that I sent him the bulk head dimensions to get the job done. I’m a big DIYer but I appreciate quality craftsmanship so naturally I love the MM overflows

 

[Pntbll687]

I would go with whatever option is most accessible for you, and the one you can repair or replace with readily available parts.

Personally, I'm not a fan of external boxes, unless the overflow goes to a room behind the tank. I like my tanks to sit as close to the wall as possible. I have a 180g drilled with an internal overflow, and it takes up maybe 18 square inches of space.

 

[NowGlazeIT]

I had 2 pillar overflows in my 120. I freed up almost 240 square inches when I took them out. The replacement takes up 18 (up high and out of the way) so I’m lovin all the extra room.

 

[Eagle_Steve]

I had 2 pillar overflows in my 120. I freed up almost 240 square inches when I took them out. The replacement takes up 18 (up high and out of the way) so I’m lovin all the extra room.

And those were not corner ones either. The corner ones are not so bad, but when off center in tank, I agree, those need to go lol.

 

[Pntbll687]

And those were not corner ones either. The corner ones are not so bad, but when off center in tank, I agree, those need to go lol.

So I have a single one of these on my 180 peninsula. I had no idea it takes up 36 square inches of space as the footprint, not to mention the vertical space.

I think in my application it's not as noticeable because I planned the scape around it.

 

[NowGlazeIT]

So I have a single one of these on my 180 peninsula. I had no idea it takes up 36 square inches of space as the footprint, not to mention the vertical space.

I think in my application it's not as noticeable because I planned the scape around it.

Peninsula with one overflow box sounds right. On one side so you get the whole rest of the tank to play with

 

[NowGlazeIT]

I’d love a peninsula on my next build. Curious what your drain type/size is on your 180

 

[BZOFIQ]

Modular Marine will make a custom size. Anything you need. I know because I went that route. Exotic Marine System would too.

Where are you located? Shipping out of US is complicated at the moment which brings up the price.....considerably.

 

[Levinson]

I would check with modular marine and fiji cube about them building you one with metric bulk heads. I am sure Will at Fiji cube would do it, and I love how quiet his overflows are. There is still the point of shipping, but if not in a huge hurry, you could just take the slow shipping time route and save some money.

There is also the option of ordering one, as is and then just doing metric to standard adaptors. Then you could use metric all the way to the sump.

This was my thought too. It’s a matter of getting the metric bulkheads ordered in and telling modular marine the fab sizes. I asked MM to cut holes for 1 1/4 bulkheads. The owner only asked that I sent him the bulk head dimensions to get the job done. I’m a big DIYer but I appreciate quality craftsmanship so naturally I love the MM overflows

Thanks for the idea! That's something I haven't thought of. I will try contacting Modular Marine and maybe some other places to ask.

I had 2 pillar overflows in my 120. I freed up almost 240 square inches when I took them out. The replacement takes up 18 (up high and out of the way) so I’m lovin all the extra room.

All that extra room! I fear I may end up regretting choosing the pillar overflow with it taking up the space. Thanks for discouraging me from going there. Though it still remains an option if the alternatives don't work out.

Modular Marine will make a custom size. Anything you need. I know because I went that route. Exotic Marine System would too.

Where are you located? Shipping out of US is complicated at the moment which brings up the price.....considerably.

I'm located in South Korea, on the other side of the pacific ocean, so not very close. You are right about international shipping being complicated at the moment, that's something I haven't thought of. Just hope the shipping is not crazy expensive.