# Rimless/ Braceless Tank - Glass Thickness



## Vinkenoog1977

Hey guys,

Just a question to check if I've done this correctly. I'm planning a largish tank at the moment, and I'm looking for an open top, rimless and braceless tank, ordinary glass, transparant silicone. Anyways, I've checked out the calculator from fnzas, but I'm not sure if I've used it correctly.

The dimensions of the planned tank are 120 x 40 x 40 cm. The above stated calculator give me a glass thickness of 8 mm. for a safety factor of 5,2, with a bending of 0,19 mm. Couple of questions:
1. Did I use the calculator correctly, i.e., are my numbers correct?
2. Will this suffice, i.e., is a safety factor of 5,2/ a glass thickness of 8 mm. enough for this style of tank?
3. Do these results mean that, when filled, the front and back panel will bend out for a maximum of 0,19 mm.?

Thanks!


----------



## Ryan Thang To

I have a 3ft tank 90x45x45 and its a 10mm glass. I would go for at lease 12mm just to be safe.
cheers
ryan


----------



## NC10

8mm seems very thin for a 4 footer. I think even a braced would be 10mm at 4 foot. Not 100% on that though.

I haven't tried the calculator but I'm currently looking for a 5ft braceless and this needs 15mm. Surely you should be around the 12mm mark at least.


----------



## Vinkenoog1977

Thanks for the replies guys, my gut-feeling kept telling me the same, however, when I started "checking my gut on the interwebs", it kept coming back with 8 mm. I even checked the ADA tanks, and, believe it or not, they are 8 mm. as well, at least the Optic White is (the Cube Garden 120P IS 12 mm.) and the 120P is slightly bigger (120x45x45). Or has Optic White glass a higher tolerance or something? 

I thought these calculators where supposed to resolve the confusion around glass thickness, not fuel it.


----------



## kirk

I'm no tank builder but I'd want at least 10mm so I could sleep at night


----------



## NC10

Vinkenoog1977 said:


> I thought these calculators where supposed to resolve the confusion around glass thickness, not fuel it.



lol

If ADA's doing it then who are we to argue? 

I suppose it comes down to budget really. Go cheap with 8mm and constantly have a doubt in the back of your mind, or over do it just to make sure.

Just to say as well, a 5ft braceless used to be made in 12mm, everyone I've contacted now has gone to 15mm. They must have learnt something from experience. Can you post a link to the calculator so I can check what it says? Just to see if it still goes with 12mm.


----------



## Vinkenoog1977

I'm going to go with 12 mm., my peace of mind if worth the extra 75 Euros.  Just for the hell of it, I will ask my LFS about what they would build it out of, out of curiosity.

This is the page with the whole story and links to the calculator. And here is the Excel-sheet, which I found easiest to work with.


----------



## Andy D

I've just ordered two tanks from ND Aquatics which are the same size of an ADA 60P (2ft wide) and they are doing it with 10mm glass.


----------



## NC10

I can't open the sheet on this, even through google drive, so I'll have a check tomorrow on the PC and let you know.  One thing I did notice though is the date on the article 

A new tank is a big expense, so an extra 75 is worth it IMO 

I still can't believe ADA do 8mm tbh. I knew their tanks were way overpriced and surrounded by hype, but the term "daylight robbery" springs to mind


----------



## Nathaniel Whiteside

My 90p is 10mm...

I'd go at least 12. Apparently the old old ADA tanks used to bow like hell on the front. 

Sack waiting for that to blow.


----------



## NC10

Nathaniel Whiteside said:


> My 90p is 10mm...



I still stand by my original statement  



Nathaniel Whiteside said:


> I'd go at least 12. Apparently the old old ADA tanks used to bow like hell on the front.
> 
> Sack waiting for that to blow.



I once had a juwel rio 400 go braceless all by itself 

Just the sound of the braces going was pretty scary, but seeing the glass bowing as much as it did was nothing short of terrifying. I measured it but can't remember exactly. It was a good inch difference at least though. I did get new braces but juwel told me it would stand up to the bowing


----------



## OllieNZ

My 120x45x45 is 10mm no visible bowing just to throw that into the mix


----------



## Vinkenoog1977

It's the bowing that concerns me most, and I want none of that! But now Ollie has me doubting about going for 10 instead of 12; would save me enough for most of the planting, but still... I'm going to pop down to my LFS tomorrow, and stop by a couple of glass suppliers nearby, and see what they come up with. For now, I'm still thinking 12 mm. is the way to go!


----------



## Rob P

I have an 80x40x40 optiwhite, in 10mm glass...


----------



## Vinkenoog1977

Well, that was an interesting morning. I visited two LFS, and two glass suppliers/ makers, and I got 3 different answers, and nearly caused a fight at the LFS. The first stop was at a LFS, and they were pretty straight forward... And told me 8 mm. would be plenty... Right... Then came the two glass suppliers; the first one was quite thorough, did some calculations, and came with a minimum thickness of 10 mm., but 12 would be better. The second glass supplier had a short and simple answer; 12 mm. 
At the second, and my regular, LFS, this question nearly caused a fight between the staff, well, let's call it a heated argument; 8 mm. vs. 12 mm. They went to and fro, threw some curse words in there, and well, decided to agree to disgree.

For me, it's clear now, and it's going to have to be 12 mm.!


----------



## discusdan

I've just build a rimless tank 700x450x400mm and used 10mm glass, No way would I consider using any thing less for a diy tank, not because the glass is too thin but because the silicone joint is not strong enough

For 1200mm tank I would personally use 12mm glass, thicker glass = bigger surface area for the silicone = stronger joint.

Bowing in the front and back pane isn't a major issue as long as it not excessive (over 3mm) and happens on all tanks.
It's pressure on the seams thats the issue, and is what causes leaks and blow outs.

In larger tanks (120l+) excessive bowing creates more pressure on the seams, the thicker the glass the less bow.
Like I said above thinner glass gives less surface area for the silicone meaning a weaker seam and thinner glass will bow more.
Thicker glass gives the silicone more surface area resulting in a stronger seam and less bowing.

I believe companies like ADA, fluval, juwel etc can use thinner glass because of the building process and silicone used.
The tanks are machine made for precision and accuracy and the silicone used it far stronger than whats available to the public.
Because of this the seams on their tanks are much stronger and so thinner glass can be used, not to mention its also more profit for them!

It would be near impossible to achieve the same precision and strength from a DIY build.

Especially if you're building the tank by laying down beads of silicone and placing the glass on top, this usually results in uneven seams that are weaker than a precision machined joint.

For this reason thicker glass is recommended for diy tanks for the increased seam strength.

Its also worth getting all edges of your glass polished.
When thicker glass is cut the break _*can*_ be uneven resulting in lumps and bumps along the length and out of square edges.
Having the edges polish should ensure they are nice and true.

Also remember silicone needs 1 day per 1 mm to cure, so if you're using 12mm glass it needs 12 days+ to cure before water testing.

Have a look into silicone injecting for building aquariums, its a slightly different process than the traditional laying beads method but you can get joint accuracy much better and its easier to do though does take a lot more time.


----------



## Edvet

My 1500 liter tank is 12mm, it's braced though.


----------



## Vinkenoog1977

Thanks for that extensive answer Dan, but, and maybe I should have been clearer, I do not intend to build the tank myself, I was just questioning what thickness I should have the tank made out of. I have room, patience, nor nerves to try out something like that as a DIY project; building stands and lighting racks, I can do that, and trust my skills enough to know it will stand the stresses and the test of time, but not with something like this; I'd like to have someone else do it, and give me a guarantee on it as well, I'm sure my insurance company, and the neighbours downstairs, will appreciate it. 

I will ask them if they use, or can use, silicone injection, and have the edges polished, and beveled. The difference between regular and injection, from an estetic point of view, is incredible, and I'm sure these guys will have access to the strongest of silicones! Going to get some quotes now, and take it from there!

Thanks for all the input!

P.


----------



## discusdan

Ah sorry my mistake, I thought you where intending on building it yourself I've got making things on the brain at the moment 

10mm should be adequate, 12mm will give you complete peace of mind if you dont mind the aesthetics of the thicker glass.


----------



## Vinkenoog1977

Yeah, I'm following your projects, awesome so far!

I'm definitely going to go for the peace of mind, and the less bow, the more peace of mind I'll have! Worth the extra money!


----------



## NC10

@discusdan - Some good points, but the major companies use thinner glass purely down to the cost. Simple as that.

Obviously it must withstand the pressure/bowing etc or they wouldn't get away with it for very long, but it's the minimum they can get away with.

Some of the top tank builders in the country just use what us mere mortals with any sense use and that's the HA6 or HA7 stuff. (can't remember which exactly of the top of my head)

It takes a lot more time, attention and work doing a DIY, but do it right and a DIY will just be as strong, if not stronger, than a mass produced tank.


----------



## discusdan

Yeah no doubt the biggest factor in using thinner glass is to maintain the highest profit margins possible and like you say as long as the tanks arn't failing they will continue to do so.

Also agree that if a DIY tank is made well it should last just as well as a mass produced tank, I used HA6 for my tank and it is strong old stuff!
I'm yet to see a DIY tank with silicone joints as refined as ADA tanks though.

DIY aquarium building gets a bad name usually from people who have rushed into building a tank with out researching correct construction methods and glass requirements, they then build a tank with undersized glass and poorly executed silicone seals and when it fails they tell every one how much of a bad idea DIY tank building is.


----------



## NC10

Yeah agreed, you're never going to get a finish like you would from a machine/robot or whatever jigs they may use.

Just as in anything really though, if you have a bit of common sense, there's no reason a DIY effort should end up a disaster.

That reminds me, I must get down to B&Q tomorrow and buy myself some anti fungicide silicone. I have some green house glass here ready to make myself a braceless 2ft deep 4 footer


----------



## Andy Thurston

Have you not seen sampiky's tank in his journal. It might not be quite as refined but its pretty close


----------

