# Derim 29 gallon aquarium



## AquaticPulse (Jun 19, 2011)

I have a 29 gallon aquarium, 36x12x15, about 15 years old. I tried to pull the rim off during a water change today. It popped right out. Looks okay without it but I put it back on just in case. 

I'm wondering now if I need to eurobrace it, or can I go rimless, or should I glue the plastic trim back on?


----------



## BillD (Jun 5, 2006)

Does the trim have a ledge for a glass top? if so, this does help with bracing some. Unless the glass is really thin the trim is likely unnecessary. However, you can either place it back on loose or stick it on with silicone. The silicone will help prevent wicking if the tank is filled to the top. I have one that size, 16" tall that is made from 1/4" glass that requires no trim.


----------



## AquaticPulse (Jun 19, 2011)

There is a very small protrusion that could possibly be used for a glass top. It came with a plastic top that sat on the edge that i have long thrown out. 

The glass i believe is between 1/4-3/8 thickness. I haven't had the opportunity to measure it as of yet. 

Did the your 16" tall aquarium come with a rim to begin with?


----------



## BillD (Jun 5, 2006)

My 32 came with 4 pieces of u-channel that covered the top edge of the glass. This was typical of tanks built in the 60s and 70s. This tank was purchased new in 1973, for $15 at Pet Fair in Hamilton. At the same time, neons were 15 for $1. They didn't count them, just scooped a bunch out of the tank.


----------



## AquaticPulse (Jun 19, 2011)

Hmm maybe i'll give it a try then without the rim.


----------



## bob123 (Dec 31, 2009)

The top trim is used to cover any sharp edges of the glass as some manufacturers do not sand the edges if it is to be covered, also it helps protect the glass from any bangs on the edges as it will chip or even crack. I would keep the trim on.


----------



## AquaticPulse (Jun 19, 2011)

I removed the top rim and smoothed the edges so its smooth to the touch l. 

Yeah I do worry about that. if any one banged my aquarium, and it tore at the seams. So I was asking if I should derim. 

But older aquariums are built to be functional with or without a rim. Unfortunately I can't find any articles to show how rimless aquariums are built and how to check if the one I have is built like so.


----------



## Fishfur (Mar 4, 2012)

Most commercial rimless tanks have machine polished top edges. It's about the only way to get that look. Doing it by hand would take forever, I think, not to mention the difficulty of getting the corners to look the same.

Even though you have smoothed the top edges, if you were to lose balance and perhaps have to put a hand on the rim with your weight, still possible to get a nasty cut if the edges aren't rounded off.

Always a chance of damage too. I have a new ten G that I just discovered has a big chip out of one outside corner. It's the size of a loonie at least.. fortunately it does not go all the way through and isn't cracked, as such. So I keep an eye on it and maybe I will fill it with glass filler, you can get the kits for windshield chips, that might work ok. Or maybe epoxy.

I'd as soon put the rim back if it were mine.


----------



## AquaticPulse (Jun 19, 2011)

Other than it's being smoothed out, how is a rimless aquarium structurally built differently than a tank with a trim on it? I've read that rimless are build so they're more enforced all around. But it sounds like it's mostly that they're rounded at the top?

I did put the trim back on it now, at least until i can figure out how they're built differently. I wouldn't want 29 gallons of water on the floor. lol


----------



## bob123 (Dec 31, 2009)

Rimless tanks are build the same as tanks that have a plastic trim, the main difference is the glass of a rimless maybe a little thicker and as mentioned the edges are rounded on the exposed edges.


----------



## AquaticPulse (Jun 19, 2011)

Does the glass thickness help with structural integrity? or is that just a cosmetic appeal for rimless tanks?


----------



## BillD (Jun 5, 2006)

The thickness of the glass is what determines the structural integrity. this is why you see rimmed tanks with centre braces. The glass shelf also adds to the strength and allows the use of thinner glass. So, while the trim helps the tank hold water safely, in some cases, it doesn't make the tank less fragile when it comes to edge hits. I have a rimmed 10 here that has glass so thin I have never put water in it.
It comes down to the individual tank as to whether the glass is thick enough to be rimless.
Having said all that, I have 4 12" x 12" x 48" tanks I built about 20 years ago from some 3/16" thick glass. On two, the centre braces popped. I was standing there when one went, and the the tank flexed back and forth. It held water like that for over a year before I got around to fixing it. The bow was about 1/2" or a bit more.
The one thing I don't like about rimless tanks is that you can see the water level, and any mineral deposits left by level fluctuations.
The one way rimless tanks may be built differently, is that some rimmed tanks have floating bottoms, where the sides go to the bottom of the trim. Rimless tanks are normally sides on bottom.


----------

