Pond Window thickness and Glass Type?

[Jwiil]

Currently working on my pond and have the plans to install a window that is approximately 8 feet to 9 feet long x 24" tall abut I am not sure the thickness or glass type I need?

Does anyone have any suggestions or guidance on what they maybe have used or what would be appropriate? The pond is going to be approximately 10' x 20' long and 5' Deep if that matters for anything I should consider.

I have noticed quite a range or material sizes and thickness, but no one really commenting on the type of glass or thickness of glass. I had one supplier recommend 9/16" ( Approx 14mm) laminated safety glass I believe it was. Doesn't seem thick enough to me but I am also no glass expert. They also said they thought acrylic would discolor after some time and start to become opaque

[aquaholic]

There is a tonne of information and similar queries online if you search.
Is your window framed in steel? Will there be a top brace? Is a little bowing acceptable?
I don't think anyone uses float glass anymore as prices and glass technology have greatly improved. The price difference between 18mm and 25mm is negligible where I am in Australia.

I've used 40mm SGP low iron laminate ( 2 x 19mm tempered sheets stuck together) in a steel frame for my outdoor concrete tank that's 1.2m deep and 7.5m long. I used 2 glass panels (each 3.6m x 1.2m x 40mm) with a narrow steel vertical post in between to reduce bowing stress and make it easier to transport and self install. You should be able find something more relevant to your size online or ask the glass manufacturer/pond reseller.

[Jwiil]

I have literally been looking online for months and have found nothing so if you have some places you have found something or links I would be super grateful. The only thing I have seen is the UK company who sells the windows framed or something of the sort. I did not have a plan for the window to be framed and was planning to cut a lip into the block work of the pond, as I've seen on many peoples ponds from the UK, and then seal between the window and pond and then liner and the window. Bowing is acceptable but I guess you could say would not be preferred.

Formal ponds (What I call them) are not very common where I am so local information is limited from pond suppliers in area. I will look up what the glass type you used translates to in the US as I am not very familiar with glass types which is part of the problem I guess you could say. Thanks for the response it was helpful to get an idea of the thickness

[coolwon]

I have a window in my pond,I was restricted to the length of about 4 feet long x 500mm deep, by the length of my face brick wall and the depth

by the cut in half railway sleeper wooden decking. A viewing and hand feeding the fish area next to my built in braai /barbecue area.

The +-3mm 316 stainless steel frame is a tig welded rectangular box shape about 4 inches deep with a reverse 90 degree bend all round to the

inside, to accommodate and support the 3/4" solid glass sealed with marine silicone.

The pond water side of the frame, is a double bend 40mm 90 degree and 90 degree 12 mm in,

I cut a slot 40 mm out from the shell opening and 15 mm deep around the perimeter of

the Gunite shell opening for the reverse angle stainless steel bent metal could fit into 15mm deep slot/groove cut around the

perimeter of the Gunite shell opening.

Come the time to install the stainless frame,I pumped a thick quantity of the sealant round the inside of thereverse flange and into the dust free \

15 mm Gunite slot. I then gentle pulled the frame into the opening with wall fixings.

The frame sank neatly into the shell opening, spreading the waterproof sealant between the gunite shell and the double bend stainless steel outer

frame.

My first glass fixing attempt using a 4,5 mm double glass laminate, cracked right across the center, while completing the face brick wall on the

outside.This crack occurred when I wiped the glass clean of building dust, using chilly tap water,and warmer pond water.

The cracked glass held up, until I managed to acquire a piece of 20 mm aquarium window glass, cut to size from the old Durban aquarium

which was relocated further down the coast to the Point Area.

My widow is a pain to keep clean of Algae

[aquaholic]

Generally speaking, it's much better to use a frame for glass since wood or blockwork surfaces are quite uneven. Angle frame to protect the side edge of tempered glass is best but I've also used simple rectangular RHS frame to hold glass and plastic angle trim for the glass edge. You need to support the weight of glass until silicone or PU has cured.

On a bigger (deeper) tank, I opted for steel as the outer frame was 10m long x 2m high. Coated with industrial rated 2 part epoxy as protective coating which has been fantastic. A 6mm spacer when applying silicone so the glass cant touch frame. Neutral cure silicone has several days cure which is more forgiving. Start the glue from top so the cold join where they meet again is also at top where there is the lowest water pressure if your slow at caulking. My glass here was 60mm thick. I used magnesium as a sacrificial anode against rust but probably being over cautious.

CoolWon - you should contact Rick at mightymagnets to simplify algae removal. I bought a set of floating magnets capable of 80mm thickness. He has cheaper and more expensive options. Fabulous but expensive at US$900 a set. They need to be stored with a spacer between as they can easily crush fingers and if they did ever touch together, you aren't able to separate ever. Goodbye $900.

About 25 years ago, I built a 1.5m deep ( 5 foot) glass aquarium using steel frame and 25mm (1 inch) float glass. Mostly successful but the float glass broke twice on different occasions, both when the tank was half empty. I suspect float glass gets a "memory" from the constant pressure, or perhaps it was a bad batch of glass. They don't make 25mm float glass anymore. Nowadays, tempered glass is cheaper and stronger.

[coolwon]

Thank you.

My labor is cheap, and he has long arms, but thanks for the suggestion.

South Africa's exchange rate is crippling.

Two kids in AUS, and two in the UK.

That's why I put up with all the $hit in South Africa, a truly beautiful country.


Would hot dipped galvanizing,not be an extra precaution on the steel frame as well as epoxy?

Our hot dipped stuff is bullet proof,and I live a good stones throw from the Indian Ocean which leaves an imprint of anything on raw steel

overnight.

[aquaholic]

Yes it's very hard to beat cheap labour for sure. I still remember growing up in Papua New Guinea as a boy, our swimming pool cleaner would get into the deep pool with a hand held brush and goggles whilst hanging onto the side with his other hand grimmly. He didn't know how to swim!! Brave bugger. Dad would also send him up onto the back of overloaded trucks to "hold down" the cargo when there wasnt enough rope...

Galvanised steel can't be used underwater. It sloths off and the zinc is toxic to fish.

There is a wide choice of commercial specialised protective coatings now. Used in highly corrosive - abrasive - harsh environments. Strong acid tanks, high octane fuel containers, etc. This link shows some products to protect steel for example - https://www.duluxprotectivecoatings....bstrate/steel/ and a similar range for other materials (concrete etc). These coatings become more essential as modern steel is significantly weaker - cheaper - lighter - less carbon - less durable than steel from 50 years ago.

I was really impressed with Dulux Duraguard STP but I'm sure other brands have equivalent. I chose this product because it can be hand painted or sprayed on. It can be touched up later and applied over old coats (no need to strip old coats off). When my steel frame got delivered the crane truck got bogged so the frame was left against a tree for 3 weeks until the ground dried out. Unfortunately the tree swayed in high winds each day causing significant rubbing (the frame was about 4 tonne weight) but amazingly the coating held up. I dive down into the tank to inspect this frame every 6 - 12 months and 5 years later, its just like new. Getting good surface cleaning via sand blasting or hand sand paper is the key. Almost any colour can be mixed in if that's important.

Steel underwater generally doesn't rust, once an oxide layer forms. It's the steel exposed to air that deteriorates. Not that I am an expert on steel but it's far cheaper and stronger than stainless as well as being easier to weld.

[aquaholic]

This link is more relevant.

https://www.duluxprotectivecoatings....age/immersion/

I did seek professional advice from their technical support and other companies before deciding but pricing, availability and my individual priorities may differ from others.

The product I chose

https://www.duluxprotectivecoatings..../durebild-ste/

[koilaria]

Sorry to hijack thread,

I'm also here in the US trying to build an above ground pond with window. I've created the pond (~1200 gallons) out of blockwork and have set an opening 4ft wide x 2ft tall into the blockwork for a window. It will be an infinity window (3 sides of support with open top). I'm coating the pond with xypex concentrate for waterproofing.

I've contacted local glass suppliers and found one that will offer 1 inch laminated glass (comprised of 2x 0.5in annealed glass) and another which is 0.75 in single pane tempered glass. Any opinions on which would be better in this case?

I'm also struggling to figure out if I need a frame. I'm considering, for the sake of how difficult it would be to waterproof frame AND window, of making a frame that surrounds the glass too just hold it in place rather than something the glass presses up against (so the glass would be sealed directly to the concrete, but would be supported by metal brackets on its sides and bottom. How does this idea sound?

[coolwon]

I used a 3 mm x 50 mm wide 304 or 316 stainless steel frame.I embedded the glass in a recognized best quality marine silicone sealer.

Approach the industrial sealing people for the most over time suitable sealant for between the frame and the pond build material.

Double laminate,110% sealed on the edges to prevent water working in between the layers of glass.

Inverted U shaped length of stainless, along the open top, to stop the UV rays affecting the sealer over time.

Always remember. Nothing but the best, is the guarantee for a DIY build.


PS Tempered glass shatters. you lose a lot of water and fish in one BREAK.

2 layers of .5 mm glass,with a membrane in between it.When it cracks it gives you time to prepare for the replacement and repair.

Been there,it cracked.I replaced it with a 2nd hand cut piece of 20 mm aquarium glass out of the Durban aquarium when they moved to their

new set up.

Poor advice from the glass suppliers representative. A temperature difference,washing the cement off the glass during the completion of a bit

of brick work completion on the outside face brick wall.

+-26 years ago.

[koilaria]

I used a 3 mm x 50 mm wide 304 or 316 stainless steel frame.I embedded the glass in a recognized best quality marine silicone sealer.

Approach the industrial sealing people for the most over time suitable sealant for between the frame and the pond build material.

Double laminate,110% sealed on the edges to prevent water working in between the layers of glass.

Inverted U shaped length of stainless, along the open top, to stop the UV rays affecting the sealer over time.

Always remember. Nothing but the best, is the guarantee for a DIY build.


PS Tempered glass shatters. you lose a lot of water and fish in one BREAK.

2 layers of .5 mm glass,with a membrane in between it.When it cracks it gives you time to prepare for the replacement and repair.

Been there,it cracked.I replaced it with a 2nd hand cut piece of 20 mm aquarium glass out of the Durban aquarium when they moved to their

new set up.

Poor advice from the glass suppliers representative. A temperature difference,washing the cement off the glass during the completion of a bit

of brick work completion on the outside face brick wall.

+-26 years ago.

Thanks!

Where did you get the frame? I don't know how to weld.

[koilaria]

Thank you! How did you build the frame? I don't know how to weld.

[coolwon]

I had a business acquaintance, who cut all the metal to size, bent it up and Tig welded the joints.

My pond was a newly Gunited shell. The window was an after thought.

Having a beer and looking through the door onto a short section of pool support face brick wall. Yea,Now is the time.

I had to a lot of thinking on how to go about it before going about cutting the opening,and how to seal it very

effectively.

The frame is a stainless steel rectangular collar. To the gunite thickness about +-100 wide

With a 90 degree bent in 50 mm lip to support the glass and have a wide enough area to add sealant to and the weight of the water to force the

glass to spread against the metal and form a wide band to increase the sealant area,tidy up outside while still wet.

On the pond side, I had bent a 50mm 90 degree facing out to ward the walls.

But I had bent a 1/2 " 90 degree section inwards bent toward the wall.

I fitted the collar in the opening,leveled it up and marked the Gunite where the inward 1/2" section would slot into after I cut the inside of the

marked perimeter.

I applied a lot of sealer on the inside of the 50mm bent section and into the slot.

This created a wide sealed area for the pond water to travel and form a leak as well as anchoring the frame all round the perimeter to reduce the

risk of the weight of the water pulling on the frame and distorting the frame,causing the glass to crack.

I used a small angle grinder to cut around the perimeter

The outside frame supporting the glass was recessed by 4 " to reduce the risk of the glass getting broken.

I had stick welded and drilled brackets to the back of the collar to anchor the collar in place prior to completing the face brick outside wall.

[SethF]

There is a tonne of information and similar queries online if you search.
Is your window framed in steel? Will there be a top brace? Is a little bowing acceptable?
I don't think anyone uses float glass anymore as prices and glass technology have greatly improved. The price difference between 18mm and 25mm is negligible where I am in Australia.

I've used 40mm SGP low iron laminate ( 2 x 19mm tempered sheets stuck together) in a steel frame for my outdoor concrete tank that's 1.2m deep and 7.5m long. I used 2 glass panels (each 3.6m x 1.2m x 40mm) with a narrow steel vertical post in between to reduce bowing stress and make it easier to transport and self install. You should be able find something more relevant to your size online or ask the glass manufacturer/pond reseller.

Where did you find the frame? Glass? Very difficult in the US. Can you provide pics or video?
Thanks in advance.

[aquaholic]

Where did you find the frame? Glass? Very difficult in the US. Can you provide pics or video?
Thanks in advance.

I really don't understand.... I did an online search for "KOI WINDOW INSTALL" and there were multiple pages of video/photo/discussions.

For example this video shows 60 cm high infinity edge which is what you are after? it's in the UK but water pressure is the same worldwide.

https://www.youtube.com/watch?app=desktop&v=NUKxXPQ30jo

If you don't like that method or don't want a frame, choose another method...

It's 25mm thick glass - single laminated. (one 12.5mm side is sufficient to hold water pressure temporarily should the other side ever fail).

I personally would have hidden the frame completely from outside view and fully waterproofed the exposed laminate edge but it's not my pond.

If you have dogs/kids/impact hazards, I would go thicker glass myself.