Will my custom made Rimless 70 gallon tank break? (Glass isnt that thick)

[asjustin]

I had a custom made 70 gallon fish tank built 2 years ago by a tank maker in Australia and only put water in it now, I've heard online that rimless tanks have a higher chance of breaking so thats why they are made with thicker glass to account for it being rimless etc.. but the glass on my rimless 5ft 70g looks kinda thin and is put together with black silcone, Im worried one day it will break also its only been filled up for 3 weeks so far with half the voulme of water inside, can having half the water the tank can put extra stress on the glass out in some way? the reason im doing this is to use less saltwater during the cycle so i waste less since i will have to empty out a good % of it out anyways

 

[Timfish]

Seems there are a couple things you can do. You could verify the thickness of your tank glass by contacting several manufacturers of tanks with the dimensions of your tank. You could also just add a middle cross support 4"-6" wide.

On a side note I always keep the original water setting up a reef system and don't see a need to dispose of it and refill with new saltwater.

 

[piranhaman00]

We need dimensions and glass thickness. It should most likely be 1/2” but potentially 3/8” depending on height

 

[asjustin]

We need dimensions and glass thickness. It should most likely be 1/2” but potentially 3/8” depending on height

The glass is 5mm thick and the tank is 20" high, 60" long and 14" wide

 

[I never finish anythi]

The glass is 5mm thick and the tank is 20" high, 60" long and 14" wide

I wouldn't trust it . Mine is 10mm thick 4x2x2

 

[colossal_tater]

Those dimensions are for a safety factor of 1. https://www.easycalculation.com/measurement/aquarium-glass-thickness-calculator.php

My understanding is that means the glass is just barely at the specs to not break when you fill it up. But that’s scary to be riding the line so close, especially on a rimless. Further more, the safety factor has nothing to do with whether the silicon will hold. With glass so thin, the silicone might not hold the glass together since there is less surface area to bond the glass pieces.

As an example, the 16” tall rimless that was made for me has 1/2” thick glass and has a safety factor of 12. That’s almost laughable in comparison to how they did you. Long story short, I certainly wouldn’t fill with water.

 

[TheBear78]

My sump is 6mm and that has glued in braces all over the place...

 

[tsharpe291]

That does seem very thin for a 5 foot tank. Assuming your tank builder is reputable I would contact them and ask the question and possibly having them install some bracing.