29 Gal Glass Tank Flex

[legoms013]

Hi I'm new here and new to fish keeping....I just set up my 30 gallon rectangular freshwater tank and have noticed that there is some "bowage" to the largest glass panels (front and back) and was wondering if this is normal. There is an 1/8" difference on both sides. I always thought glass would crack or shatter before flexing. Anyways let me know what you think, thanks.

Tanks:
1 ten gal w/fish
1 thirty gal w/ no fish

[Lady Hobbs]

Never heard of it before. I just wonder if this is a repitle tank and not a fish tank. Big difference in glass thickness. You need to check this out or the seams will give eventually, I think.

[salman]

What do you mean by "Bowage'?

[RobbieG]

Are you sure its glass and not acrylic

[dev]

Hi I'm new here and new to fish keeping....I just set up my 30 gallon rectangular freshwater tank and have noticed that there is some "bowage" to the largest glass panels (front and back) and was wondering if this is normal. There is an 1/8" difference on both sides. I always thought glass would crack or shatter before flexing. Anyways let me know what you think, thanks.

Tanks:
1 ten gal w/fish
1 thirty gal w/ no fish

Some smaller "all glass" tanks are designed without anything supporting the glass panels, and it is quite normal for these to bulge a little.

My Juwel Rekord 110 (29 gallon) is built like this. I'll go measure how much the difference is between the middle and the sides for comparison.

edit: My 110 liter (29 gallon) is 44.8 cm on the sides, and 45.2 cm in the middle, making the difference 0.4 cm, equalling 0.15 inches - or just about 1/8th of an inch.

[legoms013]

It's glass for sure, I bought it as part of Top Fin kit, so its not a terrarium tank. By "bowage" I mean the glass is bowing out a little. I can tell cause my hood does not meet up anymore in the middle. My little ten gallon tank does this too, but is much less so. Also the glass is about 2 hairs over 3/16"....I'm wondering if this is a standard thickness for this size of tank or if its too thin (it is however thicker than my ten gallon tank). I'm gonna call my reputable local fish store after a while.

At the petstore I saw some tanks with a thick plastic brace across the tank just underneath where the hood sits....and was wondering to myself why wouldn't they put one on this tank, its almost as long as those ones.

My tank is 30" Long x 18.5" Tall x 12.5" Wide

[Lady Hobbs]

Something sounds screwy. I got both my 55 and 29 gallon kits from Walmart and just measured them both. NO bowing at all. If your hood no longer even fits correctly, something is messed up. Braces are not needed on the 29 gallons.

Is your entire tank sitting supported on all 4 corners with NONE hanging over?

[dev]

My tank is 30" Long x 18.5" Tall x 12.5" Wide (inches my bad)

My Juwel Rekord tank is 31.5" long, and is bulging slighly more than yours (but the hood fits perfectly). If your tank does not have any supporting glass construction near the top, it sounds like everything is as it should be.

This really is a common tank design for whole glass tanks smaller than 160-180 liters, but if it was sold as a part of a kit and the hood doesnt fit anymore, I would definately have a word with the shop.

Lady Hobbs: Does your tank have a supporting frame, or supporting glass/plastic that is glued on near the top of your tank? legoms013: How about your tank?

[legoms013]

All my tank has is the the inch wide black plastic around the top and bottom perimeters. But no cross brace across the top. Oh and yeah it is fully supported on all edges underneath it. It sits on my homemade solid oak dresser which I'm pretty sure could withstand 400 pounds. I can't move it by myself (the dresser).

The hood stays on and everything it just has that little gap in the middle. The sides sit perfectly sqaure with the tank's plastic rim towards the corners. This is how my smaller tank is also.

Maybe as soon as I figure it out I'll post a picture.

[Kuli_Loach]

My trimming has supports on it across the top, now bowing what so ever on any of my tanks from my 5 gallon, to my 55 gallon.

[dev]

All my tank has is the the inch wide black plastic around the top and bottom perimeters. But no cross brace across the top. Oh and yeah it is fully supported on all edges underneath it. It sits on my homemade solid oak dresser which I'm pretty sure could withstand 400 pounds. I can't move it by myself (the dresser).

The hood stays on and everything it just has that little gap in the middle. The sides sit perfectly sqaure with the tank's plastic rim towards the corners. This is how my smaller tank is also.

Maybe as soon as I figure it out I'll post a picture.

A thin plastic around the top edge does not provide any support, and will bend with the glass. A supportive construction can be a number of things, most often either a metal frame, something that goes across the tank in the middle, or a long piece of glass that has been glued on to the main glass front and back.

Here is a picture of my bulging tank that has no support on the top. These tanks from Juwel have been produced in the thousands if not hundreds of thousands, and are quite safe. The 29 gallon is the largest of the Juwel Rekord models that does not have anything supporting the glass.

[Only Registered Users Can See Links.]

Most of the bulging you see on the picture is beacuse of the camera, btw. :p

I might add that my only slightly larger Juwel Rio 125 has a supportive frame and a plastic bracer. There is no bulging on this, or any of the other larger tanks - only the unsupported 110 liter design.

Most likely you have nothing to worry about, but I would check with the shop you got it in, or an LFS to make sure. Oh, and of course - the hood should definately fit :P

[legoms013]

Actually mine doesn't look like its bulging as much as yours. But yeah thats kinda what mine looks like only mine has the black frame around it. Guess this is normal.


From what you guys are saying, my tank sounds "normal" and is probably fine. I guess I have "new larger sized tank paranoia" a common illness that sets in when you buy a mid-size tank and have never had one that size before. :c12:

Thanks everyone

[legoms013]

Whats an LFS?

[legoms013]

Finally heres a picture. I think I'm maybe just paranoid.

[dev]

Doesn't look too bad, but do yourself a favour and check with the shop or the manufacturer. They are the only ones who knows for sure. If nothing else it will help you sleep at night :)

LFS is the lazy way of saying local fish store :P

[legoms013]

Sounds good, will do.

[Dave-id]

29 Gallons is about at the upper end of the range where most manufacturers install the center brace. My 33G and 30G were both braced; my 20G was not.

A bit of bowing is normal, 1/8" doesn't sound excessive to me, even my ten gallons bow out almost 1/16".

3/16" sounds like acceptable glass, but not great, especially with no brace. I remember reading somewhere that 1/4" glass is usually good for aquariums up to around 40G.

If you're worried, you could get a piece of glass cut to fit where that plastic strap would have been, and it would do the same thing. Glue it to the glass, as silicone will not stick well enough to plastic to hold.
Small pieces of glass are ridiculously cheap. I've had a few small pieces cut by assorted glass shops, and rarely ever been charged more than about $3 / piece. Just ask them how much it would cost before you order.

[dev]

Actually mine doesn't look like its bulging as much as yours.

Just noticed this one. My tank is not bulging as much as it seems on the picture, you would hardly notice it when looking at the tank. Most of that comes from the optics on my camera :)

[legoms013]

I might do the glass brace thing, thats a good idea. Well I won't worry about it to much anymore. Thanks everyone.

[salman]

When you bought the tank, did it have a 'bowage'? or did it just come? Some tanks are designed with bowage. If you cant close the aquarium cover, take it back to the place you bought it and demand for a refund or an exchange.

[legoms013]

When I bought it it was square. The water weight and pressure has pushed it out just a tad though.

The aquarium hood closes, its just theres a small gap (1/8") between it and the plastic frame. I guess it's alright though from what everybody is saying....some are saying its even worse on theirs so I don't have to worry abought it.

Shoulda bought a bowfront so it wouldn't matter........

Oh well, I'm happy with the way it looks and it's size.....Its a very good size for my room and plenty roomy enough for most small fish (but not for my favorite: bala sharks).