# Other Aquarium Forums > Marine Tanks >  glass thickness for marine.

## ranmasatome

Hi,
Okay..so i'm a newb when it comes to marine tanks but i want to start one...the thing is i just got this 3ftx1.5x1.5 tank for free today its got 3 glass braces siliconed and going across the top width of the tank. i wanted to use it for a marine tank but heard that since the water is denser and since i'm gonig to be putting live rocks in there that it may bow, crack, or just welll....just not good things.
the glass on this tank is only 6mm....should i change to a 10mm one? is this necessary? and if i dont change..how probable is there a chance of something going wrong? Can i even use this tank? thanks for all the input guys..i'm lokking forward to it.. what do you reccomend?

----------


## ranmasatome

no one knows ar? or no opinions?

----------


## mikehooi

i m not sure about this,last time i heard my fren said the tank need to be very thick but i found it is a bit not true,cos i just start a nano tank which i got free from my fren very small and the glass very thin but it still survive.

----------


## Terryz_

The bigger the tank... the thicker the glass must be... for a 3ft tank the minimun should a 8mm or 10mm...
Becos the nano tank is small so the water pressure on it is not that high... so the glass is still able to sustain it...

----------


## BFG

Yup, tanks for marine need to be thicker. I have seen a 3ft 6mm tank bow. The owner was just using it temporarily to house his marine livestock as his main tank has leaked. 10mm should be enough. 

As for bracing, there is another type called Euro bracing.

----------


## tawauboy

salt water is only slightly heavier than fresh water. specific gravity of about 1.02. it's the amount of live rock that really matters.

----------


## Livaio

> Hi,
> Okay..so i'm a newb when it comes to marine tanks but i want to start one...the thing is i just got this 3ftx1.5x1.5 tank for free today its got 3 glass braces siliconed and going across the top width of the tank. i wanted to use it for a marine tank but heard that since the water is denser and since i'm gonig to be putting live rocks in there that it may bow, crack, or just welll....just not good things.
> the glass on this tank is only 6mm....should i change to a 10mm one? is this necessary? and if i dont change..how probable is there a chance of something going wrong? Can i even use this tank? thanks for all the input guys..i'm lokking forward to it.. what do you reccomend?


For 4ft is 10-12mm. for 3 ft is 8-10mm. etc

----------


## armani

yeah, for 3ft minimum should be 8mm...

----------


## kelstorm

> Hi,
> Okay..so i'm a newb when it comes to marine tanks but i want to start one...the thing is i just got this 3ftx1.5x1.5 tank for free today its got 3 glass braces siliconed and going across the top width of the tank. i wanted to use it for a marine tank but heard that since the water is denser and since i'm gonig to be putting live rocks in there that it may bow, crack, or just welll....just not good things.
> the glass on this tank is only 6mm....should i change to a 10mm one? is this necessary? and if i dont change..how probable is there a chance of something going wrong? Can i even use this tank? thanks for all the input guys..i'm lokking forward to it.. what do you reccomend?


So sorry for the delay. was busy with work. 

It will be too thin unless u are keeping just water and sand and no live rocks and perhaps a blue spotted ray. In that case, it should suffice but i would not risk it if i were u coz the last thing u need is to have the tank giving way.. minimum is 8mm... in fact for my 4ft, i, using 12mm.. will be using 15mm for my new 5ft tank in my house.

----------


## lightbolt75

Too think bro. Unless you want to come back to a house full of salt water everywhere. Better play safe and use at least 8mm... although 10mm will be better. Cos it is saltwater... dun take chances... better to buy a new tank. U never know where there will be a leak in 2nd hand tanks.

----------


## uyopong

The thicker the glass,more surface area for the sealant/silicone to bond,,means your tank will be solid and sturdy.
The thicker the glass the greener it will appear.(normal glass)
Thicker glass doesn't mean it will not bow or leak,depends on the tank maker skills and type of sealant used and positioning of braces.

----------


## limsteel

how about 2ft is 6mm enough? my current tank 2 x 1 x 1.5 is 6mmm and it is doing fine for 6 mths...

I just got a 2ft x 2ft x 21inch 6mm also. estimated about 180ltr of water... almost the same as a 3ft tank... can do up a marine?

----------


## kelstorm

it should be fine but i would prefer to play it safe by using 8mm.

----------


## piglet

my own experience... had a 2.5footer freshwater tank which i converted it to a marine tank 6-7years ago.. running this tank for 1yr+ without any problem.. one fine day, the front panel gave way. 

so it is really better to get a thicker glass (10mm~safer) with stronger silicone plus full bracing for the tank.  :Wink:

----------


## kelstorm

the last thing u need, is to come home to a 'swimming pool' with dead fishes on the floor after a hard day work.. that can clean up but if u have nice furniture ard.. all i can say is good luck...  :Opps:

----------


## Darylyap

Hi ranma, hope i'm not too late...
The pic of my tank at "mixing" thread is 3(L)x1.5(D)x2(H), glass thickness is 6mm, with 30kgs of LRs.
was my former planted tank. started marine mid last year.
so far no bowing and stuff.
but take note mine has wooden reinforcement (with silicon) on top of tank.

----------

