The top of my tank has bracing all over the 4 sizes, so that a lid can easily be put on it. However, I just bought a new hang on filter, and misjudged it. The only way now is to remove one of the bracings and use the edge to hang my filter. How to I cut through the silicon?

We've used a very sharp craft knife... and scalpel

I have also used a Glass cutter to cut the amount of brace of required leaving most of it still there

Then using a sharp blade cutting away the silicon

Brad

And I have used a glass cutter and removed only the part of the brace required, leaving the remainder of the brace intact.

are you sure the tank will be secure with out the bracing?

I am facing a very similair dilemma to you at this very moment

What are your tanks dimensions??

My tank (in cm) is 1200longx600tallx700deep.

My tank is a 3footer. I'm sure my tank can survive without the bracing off one side of the tank, and the main reason it was put there was to ensure the lid would be able to fit properly on the tank. Will try to put up pics soon.

If you remove a small amount of bracing take it from tha end rather than the back

It's quite hard to explain but I think its actually safer to take it off the back. Hold on, when I get the chance to find the camera I'll put a few pictures on.

The bracing wants to be on the longest side because that is where the most flex is.

Post the exact tank dimensions and glass thickness and I'll calculate if it's safe for you to remove the bracing...

Alternatively, return the HOB filter and get something that fits

Alternatively, return the HOB filter and get something that fits

Exactly my thoughts, as its 100% safer on the tank and less work. A Canister one would be ideal. As far as I know, the bracings along the front would hold more stress than the sides. Id rather change the filter than risk of bowing or cracking the tank. Just my 2c. Ive seen 3footers and 4 footer give way without adequate bracings..

If your tank is made properly there should be virtually no gap between the glass and bracing to get a razor into. If so, use a glass cutter to create a score and then use pliers to gently twist the glass at the score and make a crack in the bracing, then simply push the unwanted glass up and down to loosen it and then have at the silicone with a razor blade - craft knife, etc - until it comes off.

note - remove a bit from an end of the bracing rather than a chunk from the middle.

All advice given is for your info only. I think I agree with everyone here when I say anything you do to your tank is your own responsibility

Alternatively, return the HOB filter and get something that fits

Duh, why didn't I think of that...

I cant find the camera, so I've drawn a picture instead.

The red part is the one I want to remove. I think the main bracings would be the ones running from top to bottom, where else the one I want to remove would be a side bracing maybe? Underneath the bracings are another piece of glass, so that the covers can be put on it.

If thats still not clear, I'll go borrow a camera. My tank dimensions are 900x450x450.

Edit - Picture had problems, and the drawing is not to scale.

And glass thickness?

Usual standard. 6mm was it?

Ok, if it is 6mm, your current safety factor is 2.37 with 0.41mm deflection of the glass. If the bracing is removed, your safety factor will drop to 1.71 and 4.95mm of deflection (thats approx 72% of the current strength of the tank and 1207% increase in deflection) . It's up to you if you think 1.71 is enough... I still think your best option is the change the filter.

I assume the higher the safety factor the better? Whats the lowest it could go? (Not that I want to remove more bracings of course ..) But I should mention that underneath the bracings there are a few more piece of glass to hold on to it. Will that affect the safety factor?

There are better guru's on here.. But I think I read in a previous post that 1 would work forever in a perfect world with perfect glass and a perfect base no movement etc..

But if you bump the glass or the glass is chipped or slightly weak it wont work..

It also depends on how it is braced. Your drawing could be interpreted a number of ways and as for the other bracing ???

Will try to describe it in a bit more detail.

Assume the top has nothing on it yet. There are 3 bracings, left right and center of the tank. These are running from top to bottom. Underneath these bracings are smaller pieces of glass, to provide a ledge for the lid to sit on.

The side bracings are sitting on the ledges at the side of the tank, and are siliconed together. I hope that made sense.

Edit - Spelling error.

When I brace a tank I use 10 or 12 mm glass right around the top inside the tank about 10mm down from the top and the lid sits on that level with the top of the tank. In my view straps across the top are no good compared to "euro bracing". When I was making tanks I had to repair a few and they were all strap braces,thats why I don't like them.

I cant find the camera, so I've drawn a picture instead.

The red part is the one I want to remove. I think the main bracings would be the ones running from top to bottom, where else the one I want to remove would be a side bracing maybe? Underneath the bracings are another piece of glass, so that the covers can be put on it.

If thats still not clear, I'll go borrow a camera. My tank dimensions are 900x450x450.

Edit - Picture had problems, and the drawing is not to scale.

You will be fine to remove that brace.

Can't see how it would reduce the safety factor as much as Warren said.

Alot of 3ft tanks only have bracing on each end and thru the middle.

Go for it.